Ba enteric ey nae z He aban TRANSACTIONS OF THE, WAGNER FREE INSTITUTE)... OF SCIENCE Ok Fea lelaeAND) Ee retell VOL. IIL. PART IV. INTE IR WAG 8s.) 8) WAGNER FREE INSTITUTE OF SCIENCE MONTGOMERY AVE. AND SEVENTEENTH ST. PHILADELPHIA ora Ky 20 al ne J CONTRIBUTIONS TO THE PER IARY SHAWNA OF FLORIDA WITH ESPECIAL REFERENCE TO THE SILEX BEDS OF TAMPA AND THE PLIOCENE BEDS OF THE CALOOSAHATCHIE RIVER INCLUDING IN MANY CASES A COMPLETE REVISION OF THE GENERIC GROUPS TREATED OF AND THEIR AMERICAN TERTIARY SPECIES BY WILLIAM HEALEY DALL, A.M. PALEONTOLOGIST TO THE UNITED STATES GEOLOGICAL SURVEY ; HONORARY PROFESSOR OF INVERTEBRATE PALEONTOLOGY IN WAGNER FREE INSTITUTE OF SCIENCE PART IV. I. PRIONODESMACEA : NucuLta To JULIA Il. TELEODESMACEA: TEREDO TO ERVILIA WAGINIEI leiRels UNS UONUTe “Ol SOWaInGls Ole JelsVEAD sie lshuay TRUSTEES SAMUEL WAGNER, President. RICHARD B. WESTBROOK, Treasurer. JOSEPH WILLCOX, Secretary. J. VAUGHAN MERRICK, JR. S. T. SKIDMORE. HARRISON S. MORRIS. SAMUEL TOBIAS WAGNER. IVNCWILIN HENRY LEFFMANN, A.M., M.D., President of the Faculty. S. T. WAGNER, B.S., C.E., Secretary of the Faculty. $ HENRY LEFFMANN, A.M., M.D., Professor of Chemistry. J. T. ROTHROCK, M.D., S. T. SKIDMORE, A.M., Professor of Botany. Professor of Physics. W. B. SCOTT, A.M., ROBERT ELLIS THOMPSON, A.M., Professor of Geology. Professor of History, Literature, and Political Economy. S. T. WAGNER, B.S., C.E., THOMAS H. MONTGOMERY, Jr., Ph.D., Professor of Engineering. Professor of Biology. WILLIAM HEALEY DALL, A.M., Honorary Professor of Invertebrate Paleontology. THOMAS L. MONTGOMERY, A.B., CHARLES W. JOHNSON, Actuary and Librarian. Curator of Museum. Bure a ‘SAS a lente e ails . HE following pages are in continuation of the work on the Tertiary Fauna of Florida which was published in the preceding parts of this volume. As it was thought by persons interested that the title of the work insufficiently indicated its present scope, it has been supplemented by one or two explanatory lines on the title-page. When this work was begun the scheme included chiefly a description of the entire invertebrate fauna of the Pliocene beds of the Caloosahatchie, the silex beds of Ballast Point, and other Floridian localities explored by Mr. Joseph Willcox, Professor Heilprin, the writer, and others, with such refer- ences to allied forms as might be necessary for the proper elucidation of the material. As time went on, however, the interest aroused by the explorations of the Wagner Institute and its friends, and by the United States Geological Survey in Florida and adjacent parts of the Coastal Plain, resulted in bringing in a constantly increasing mass of material. In particular, the existence of Upper Oligocene beds in Western Florida, containing hundreds of species many of which were new, added two populous invertebrate faunas to our Tertiary series. It was found that a number of the species belonging to these beds had been described from the Antillean Tertiaries. Hence it became necessary, in order to put the work on a sound foundation, not only to review the species of any given group known to occur in the United States, but also to extend the revision to the Tertiaries of the West Indies. Owing to the chaotic condition of our Tertiary Paleontology, especially the Post-Eocene faunas, this work has involved an enormous amount of drudgery, occupying the writer’s leisure to an extent not anticipated at the outset. It is believed that the results will be beneficial in clearing the way for subsequent students and putting the nomenclature on a more permanent and reliable basis. The clearing up of the stratigraphical relations of many of the older species is quite as important as the description of the numerous vii vill PREFACE new ones which have turned up in the course of the work. It is hoped that another part will conclude this series of papers, and comprise, besides the remaining descriptions, a summary of the faunal population of each of the principal Neocene horizons. To Dr. Charles D. Walcott, Director of the United States Geological Survey, to the authorities of the Smithsonian Institution and National Museum, and to numerous private correspondents and colleagues, thanks are due for facilities accorded and assistance rendered in the prosecution of the work. Witiiam Heavey DAL. TE ARY EAUNATOL FLOR TD A ¥ Order PRIONODESMACEA. Superfamily NUCULACEA. Famity NUCULID&. Genus NUCULA Lamarck. Nucula Lam., Prodr. Nouv. Class. Coq., p. 87, 1799. Type Arca nucleus Linné. Nuculana Link, Rostock-sammlung, p. 155, 1807. Glycymerts Da Costa, British Conch., p. 170, 1778, ex parte. N 1778 Da Costa proposed for the Chama glycymeris of Belon (1553) and the Arca nucleus of Linné a genus under the name of Glycymeris. In his System of Conchology published two years previously Da Costa had not adopted the Linnéan nomenclature, but in his British Conchology and later in the Museum Colonnianum, which tradition says Da Costa edited from a manuscript of Hwass for Humphrey, he used the binomial system. The name Glycymeris had not previously been used by any binomial author, for Klein, who is sometimes erroneously cited for scientific names, cannot by any stretch of courtesy be truthfully called binomial. In the same work Da Costa used the generic name Pectunculus, subsequently applied by Lamarck (1799) to the orbicular Arks, for the group which had already received the name of Venus from Linné. Da Costa’s Glycymeris was intended to include all the rounded bivalves with a Taxodont hinge. Those of the type of Chama glycymeris were erected by Lamarck into a genus Pectunculus in 1799, leaving, according to modern rules of nomenclature, for Glycymeris Da Costa only the Arca nucleus and its congeners. I confess I am unable to see how a con- sistent application of our rules, if we accept Pectunculus Lamarck, can avoid the use of Glycymeris for the group usually called Mucula. Pectunculus pre- ceded Nucula in Lamarck’s Prodrome, and consequently must first be disposed 571 TRANSACTIONS OF WAGNER 2 57 TERTIARY FAUNA OF FLORIDA of. If, on the principle of *‘once a synonyme always a synonyme,” we reject Fectunculus Lamarck, on the ground that the name had already been used for another group by Da Costa in binomial form, we could then retain Lamarck’s Nucula at the cost of adopting Glycymeris for the group usually called Pec- tunculus, which is probably the least inconvenient arrangement of the two. According to Herrmannsen Glycymeris was used by Belon, or Belloni, in a quasigeneric sense two hundred years before its use by Klein; so, even if we resort to non-binomial authors, the latter’s name would have no standing. This is probably the reason why Da Costa, who was a man of erudition not prejudiced against the non-binomial writers, adopted the name in its original sense. I have already pointed out that the name WVcu/ana of Link is merely a modification, on the score of taste, of Mucu/a Lamarck. Link was enumerat- ing the Rostock collection, and since it happened that they had only one species, JV. rostrata (since separated as Leda by Schumacher), to represent the genus, it follows the modified name; but there is nothing in this fact nor in the diagnosis of Link to intimate that he intended to subdivide the original Nucula, Wink altered many names in this fashion, of which Achatium, for Achatina Lam.; Anatium, for Anatifera Lam.; Cassidea, for Cassis Brug.; Cerium, for Cerion Bolt.; Harpalis, for Harpa Lam.; Limaria, for Lima Lam. ; Nassaria, for Nassa Lam.; Pectinium, for Pecten Mull.; Pleurotome, for Pleuro- toma Lam.; Tridachne, for Tridacna Lam.; Unionum, for Unio Retz., etc., are examples. For this reason I can only regard Muculana as an absolute and exact synonyme of Mucula Lamarck. Subgenus ACILA H. and A. Adams. The divaricately sculptured Nuculas in this group, in the recent state, are Pacific in their distribution; one species, V. divaricata Hinds, extending from Korea (as WV. mirabilis Ads. and Rve.) to the China Seas (JV. zvs¢gnis Gould) and probably to the Bay of Bengal (JV. Fidtoni Smith), reaches a length of thirty millimetres ; another, distinguished by smaller size, more ovate form, and a fine, regular, concentric over obsolete divaricate sculpture, is only known from Northern Japan (JV. japonica Dall); another still (VV. dvaricata Val., + cas- trensis Hinds, + Lyalli Bd.) extends from the Aleutian Islands to California. In time the group recedes to the Cretaceous, with a much wider geographical range; two species are known from the Greensand of Europe, one (VV. Armani Girard) from the Upper Cretaceous of Alaska at Atka Island, another from the FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA 573 Chico of California CV. éruncata Gabb) which is reported by Gabb to extend upward into the Tejon Eocene (Pal. Cal., i., p. 198, pl. 26, fig. 184; ii., p. 197). An examination of undoubted Cretaceous specimens of WV. fruncata shows that the species differs from the Tertiary forms by its more impressed escutcheon, its finer and more delicate divaricate sculpture, and its more prominent close set, regular and even concentric sculpture. Those I have seen are also smaller. They are quite distinct from WV. Evmani, which may eventually prove to be of Tertiary age. Some confusion has been caused by the too inclusive manner in which Gabb has treated the fossil forms of the Pacific coast. I find a large Eocene species which is not distinguishable from JV. decésa Conrad, the latter being a second name for JV. divaricata Conrad (1848), not of Valenciennes (1833), nor of Hinds (1843), which was afterwards named (WV. Conradi by Meek (S. I. Miocene Checklist, p. 27, 1864). This probably extends into the Miocene, and to assist in clearing up the difficulty I have included a figure of it (plate 40, figures 1, 3). In unmistakable Miocene of Oregon, on the Nehalem River, near Mist, Columbia County, another form is found of smaller size and much coarser sculpture, the posterior end more distinctly rostrate, but other- wise very similar, for which I propose the name of Mucula (Acila) cordata (plate 40, figure 4). The interesting point, however, is that none of the fossil forms can be properly united with the recent .V. divaricata Val. in spite of Gabb’s opinion. The latter is a more trigonal, compact, and less rostrate form, and clearly distinct. The fossil forms are more closely related to the recent species of Japan than to the existing west American shell. Like many other Pacific groups, Aci/a extended to the Antillean region through the gaps between the Central American archipelago in Oligocene times. It is represented by WV. Schomburgki Forbes, from the San Fernando beds of Trinidad, which differs from the west American fossils by its more rostrate shell, and by WV. tuberculata Gabb, from the Oligocene of Hayti. It is possible that deep-sea dredgings will eventually reveal a surviving species in the abysses, but to the present time no recent species is known from the Atlantic and only the WV. Codboldie from the Pliocene of the British Crag beds. No east American fossil species is known at all from the continent of North America. The species have, as a rule, twenty to twenty-two antérior and nine to eleven posterior teeth; the posterior tooth in the left valve nearest the chondrophore is larger than those immediately behind it. All the species have concentric sculpture. TRANSACTIONS OF WAGNER 574 TERTIARY FAUNA OF FLORIDA _ Subgenus NUCULA s. s. The Neocene species of Vucula are quite puzzling, owing to the close similarity of all the species in a general way, and the variability of each in minor details. Nucula proxima Say. Nucula proxima Say, Journ. Acad. Nat. Sci. Phila., 1st Ser., ii., p. 270, 1822; Tuomey and Holmes, Pleiocene Fos. S. Car., p. 53, pl. 17, figs. 7-9, 1855 ; Emmons, Geol. N. Car., p. 287, fig. 208 B, 1858; Dall, Bull. 37, U. S. Nat. Mus., p. 42, pl. 56, fig. 4. Nucula obliqgua Say, Am. Journ. Sci., il., p. 40, 1820; not Lam., 1819. Older Miocene of New Jersey at Shiloh and Jericho, Burns; Yorktown beds of Virginia, Harris; north end of the Dismal Swamp, Virginia, Shaler ; Pliocene of the Caloosahatchie and Shell Creek, Florida, Willcox and Dall; Pleistocene of Simmons Bluff, South Carolina, Burns; recent: (typical form) from Charlotte Harbor, Florida, northward to North Carolina in two to one hundred fathoms; (var. ¢vnculus Dall) from Long Island Sound northward to Nova Scotia. If a geographical series of this species be examined, it will be noticed that the northern specimens are almost smoothly truncate behind, the es- cutcheon is not impressed to any marked degree, and there is no angle at the margin below the escutcheon. On the other hand, the specimens from the southern coast, whence Say’s type was derived, have a thinner shell with an impressed escutcheon, the middle of which pouts more or less strongly; the valve-margin below the escutcheon has a projecting angle; the shell is some- what compressed, compared with the northern form, and has a paler and more delicate epidermis. Several of these characters are correlatives of the latitude, but the extreme forms without a connecting series would be taken by any careful observer for distinct species. Most of the conchologists of the United States having resided north of Delaware, the northern form is the more familiar both in books and collections, but it is not the original type, and I have therefore given it a varietal name. The fossils, so far as yet observed, are all more like the variety ¢rwnculus, corresponding to the cooler temperature of the sea in this region during Miocene times, while the Pliocene specimens are rather undersized, which may have been the result of the increasing temperature which characterized that epoch in Florida. There is little doubt that the original Maucula obfiqua of Say, from the Miocene of Petersburg, Virginia, was a variety of JV. proxima ; at any rate, the FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA 578) specific name had been used by Lamarck a year before it was applied by Say to the fossil, so that for the American shell the name must be discarded. Nucula Shaleri Dall. PLATE 40, FIGURE 6. Nucula Shaleri Dall, Am. Journ. Sci., xlvili., p. 298, Oct., 1894. Miocene gravelly conglomerate of Chilmark, Martha’s Vineyard, and in the Pliocene of Gay Head; J. B. Woodworth. This large species belongs to the group of WV. decussata and antiquata Sby., of which the recent representative on our coast is the small WV. crenulata Hinds. Lon. of shell 15, alt. 11, diam. 7 mm. There are eight to eleven anterior and sixteen to twenty posterior teeth. Nucula chipolana n. s. PLATE 32, FIGURE 10. Oligocene (“Old Miocene’’) of the Chipola beds, Calhoun County, Florida, and of the lower (Chipola) bed at Alum Bluff, Appalachicola River, Florida ; Burns and Dall. Shell small, solid, polished, with faint radial stria more conspicuous ventrally, and more or less obvious incremental lines; breaks turgid, low; posterior end of shell obliquely truncate, flattish ; base arcuate, anterior dorsal line sloping, anterior end attenuated and rounded; there is no defined lunule; the escutcheon is elongate-cordate, ill-defined, the margins in the middle line slightly pouting; internally polished, hardly pearly, with the basal margin finely sharply crenulate; the chondrophore small, narrow, and very oblique, anteriorly directed; anterior teeth narrow, slender, about thirteen, posterior teeth four or five. Lon. of shell 4, alt. 2.75, diam. 20 mm. The chief characteristics of this small species are its elongated form and fine radial striz. Nucula sinaria n. s. PLATE 32, FIGURE 7. Oligocene of the Alum Bluff beds on the Yellow River at Oak Grove, Santa Rosa County, Florida, and Miocene of the St. Mary’s River, Maryland ; Burns and Harris. Shell small, solid, trigonal, polished, with fine radial strive, more distinct near the basal margins, and faint, concentric, rather irregular furrows, obsolete TRANSACTIONS OF WAGNER 576 TERTIARY FAUNA OF FLORIDA over most of the valve, but tending to be stronger near the anterior and posterior slopes; here and there one crosses the whole shell like the indication of a resting stage; dorsal slopes nearly straight, base arcuate, ends rounded; lunule absent, escutcheon impressed ; striated, the margins not pouting in the middle; beaks prominent, obtuse; interior brilliantly pearly, muscular im- pressions deep; the basal margin finely crenulate; hinge strong, wide; the chondrophore oblique, heavy; anterior teeth wide, strong, about seventeen, posterior about seven. Lon. of shell 4.75, alt. 4, diam. 2.5 mm. This species differs from the preceding by its more trigonal, heavy, and pearly shell, its wider and proportionately heavier hinge, and its impressed instead of merely flattened escutcheon. The Maryland specimens are usually larger and more worn than the types from West Florida; both retain a purplish tint in their nacre. Nucula taphria n. s. PLATE 32, FIGURE 14. Miocene of Magnolia and the Natural Well, Duplin County, North Caro- lina; Burns. Shell small, very solid, rounded cuneiform, with few strong, distant con- centric grooves, like marks of resting stages, which extend clear over the shell, otherwise smooth; beaks prominent, turgid; lunule absent ; escutcheon faintly indicated ; posterior end subtruncate, anterior produced and rounded, base moderately arcuate; interior hardly nacreous, muscular impressions large and distinct; basal margins entire; hinge strong and heavy; chondro- phore wide, distinct, a little oblique; anterior teeth thirteen, posterior six or seven. Lon. of shell 2.9, alt. 2.25, diam. 1.5 mm. This interesting species is related to the recent WV. del/phinodonta Mighels, which is a more rounded and less oblique shell, without the strong concentric grooves of JV. ¢aphria, Nucula prunicola n. s. PLATE 32, FIGURE 9. Miocene of Plum Point, Maryland, Burns; and one mile south of Plum Point, Harris. Shell small, inflated, polished, very inequilateral ; surface with obsolete, ‘obscure radial striae, stronger where they cross between the concentric ridges and near the ventral margin; beaks, dorsal slopes, escutcheon, and the poste- rior two-thirds of the sides of the shell smooth or nearly so; on the anterior FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA Oa, third sculpture of moderately elevated concentric lamella separated by wider radially grooved interspaces; these lamella break off abruptly anteriorly, and posteriorly become gradually obsolete in front of the middle of the shell; they are strongest in front and near the margin; lunular area lanceolate, large, not impressed, marked by the cessation of the lamella; escutcheon roundly cordate, impressed; the margins pouting in the middle; there is no circum- scribing line; beaks turgid, recurved; interior brilliantly pearly, the basal margin strongly crenulate, the muscular impressions feeble; base arcuate, ends rounded; chondrophore narrow, not prominent, anteriorly directed; the anterior line of teeth long, slightly arched, the posterior meeting it at nearly a right angle, short, straight; anterior teeth about twenty, posterior six or seven. Lon. of shell 6, alt. 4.5, diam. 3.75 mm. This is a very remarkable species which cannot be confounded with any other recent or fossil in the United States. Other Tertiary species of Mucula known in North America and the Antillean region are as follows: From the Eocene: JV. ovala Lea, Midway and Claibornian ; WV. mediavia Harris, Midway; NV. magnifica Conr. (+ NV. Sedg- wick Lea), and NM. monroensis Aldr., from the Claibornian; WV. meridionalis Mey. and Aldr., and WV. sphentopsis Conr., from the Jacksonian; from the Oligocene: LV, vicksburgensis Conr.; from the Miocene: JV. diaphana and NV. dolabella H. C. Lea, and WV. cuneiformis Conr, (1848, Astoria), not of Sowerby ; from the Pliocene: JV. eazgua Sby. (San Diego, California, Well), VV. daccata Guppy, JV. crenulata Hinds (+ WV. vieta Guppy and WV. tenuisculpta Gabb), and WV. imonensis Gabb; NV. expansa Rve. is reported from the Pleistocene of Hudson Bay, also with JV. ¢enuzs Mtg., its variety zzflata, and NV. antiqua Morch, from the Leda clays of the northeastern United States and Canada. It is not necessary to mention here the species described as Nucula and since referred to Voldia or Leda, which will be found under those genera respectively, but I may note that WV. carinifera Lea is the young of Limopsis cuneus Conr., VV. equilatera H. C. Lea is a Crenella, and NV. pectuncularis Lea should be referred to 7rznacria. Famitry LEDID/:. Genus LEDA Schumacher. This genus is the Waculana of Adams, Meek, and others, but not of Link. It has been divided by authors into a multitude of sections, subgenera, TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA 578 etc., some of which are convenient, but all intergrade as far as can be judged from the shells, though the extreme forms are very distinct. The number of species is probably larger than that of any other American Tertiary genus. They often require very critical treatment, and, unfortunately, very few have been adequately described, figured, or compared. Descriptions based on internal casts are of value only as indicating the presence in the horizon concerned of the genus or its near relatives. It would be impossible to identify a species from such data with any certainty. Yet quite a number of names in American lists rest on no better basis. A thorough review would probably increase the number of species while rejecting a certain pro- portion as unidentifiable. Much carelessness has also been shown in using preoccupied specific names for new American forms. Both Gabb and Conrad have given entirely distinct species at different times the same specific name, and names already applied by European writers to species of Leda have been repeatedly used for new species here. A few of these errors will be corrected here, but the subject needs a monographic revision. Among the older Eocene species Leda milamensis Harris, L. quercolls Harris, L. Aldrichiana Harr. (elongatoidea Aldr. var. ? Harr., Midway, Bull. 4, not of Aldrich), Z. saffordana Harr. (= protexta Gabb, pars), L. robusta, L. corpulentoidea, and L. elongatoidea Aldr. have been described; to which will be added here two apparently undescribed forms from Wood’s Bluff. The Claiborne and Jackson, or Middle Eocene group, has a larger number, some of them very peculiar species, of which we may enumerate Leda alt- rupiana and L. (Adrana) aldrichiana Harris, L. equals Conr. (non Reuss ? + ? media Lea, non Wissm.), L. bastropensis Harr., L. bella, L. celata (not of Hinds), and ZL. calcarensis Conr.; L. culteliformis Rogers, L. houstonia Harr., L. tmprocera Conr., L. (Adrana ?) lsbonensis Aldr., L. magna and media Lea (? + carolinensis Conr.), L. Vanuxemit Dall (L. mucronata Conr., 1847, not of Sowerby, 1825), Z. opulenta Conr., L. parva Rogers, L. plana, plicata, pulcher- rima, and semen Lea, L. semenoidea Aldr., L. subtrigona Conr., L. smirna Dall (LZ. eborea Conr., 1860, not of Conr., 1846), L. Znxifera Conr., L. mater Meyer, L. multilineata Conr., and a new form now described from Wahtubbee. The Oligocene, except in the Antilles, is less populous with Leda, but offers L. parilis and serica (not sericea) Conr. from the Vicksburgian, which also includes L. maltilineata Conr., and from the Upper Oligocene ZL. acuta Conr. (1832, not of Sby., 1837, or Gabb., 1873), LZ. foridana Conr. (probably never described), L. flexuosa Heilprin, and ZL. tellinula Conr. From the Oligocene FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF. FLORIDA On ~wI Ne) of the Antilles we have L. zdigena Dall (L. disulcata Guppy, 1867, not of Meek, 1861), Z. clara Guppy, L. lecta Guppy, L. Packeri Forbes (+ incognita Guppy), Z. peltella Dall (pl. 32, fig. §; = acuta Gabb, 1873, not Conr., 1832), L. Guppyi Dall (Cercomya ledeformis Guppy), L. perlepida Guppy, and an un- described species of Z?xdaria. here are several Darien species, probably new, but as yet represented by material insufficient for full description. In addition to the species which persist from the Oligocene and the new forms about to be described, the following are known from the North Ameri- can Miocene: L. acutidens and carinata H. C. Lea, L. concentrica Say (+- eborea Conr., 1846), L. Hictata Conr., L. vitrea Orb. (+ Millert Gabb), and the Cali- fornian ZL. penta Contr. In the Pliocene there appear newly only ZL. manensis Gabb of Costa Rica, and on the Pacific side ZL. peruviana Dall (acuminata Nelson, 1870, not von Buch, 1845) and ZL. faphria Dall (L. celata Hinds, 1844, not Conr., 1832); while from the Pleistocene of Maine we have ZL. Jackson Gould (1841, + buccata (Stp.) Moller, 1842). The Ledas have been divided into a number of groups variously regarded as sections, subgenera, or even genera. A synopsis of the principal ones may be of use to students, and is here given before proceeding to describe the species. I refer only to those represented in the Tertiary. Subfamily LEDIN 2. Genus LEDA Schumacher, senso lato. A. Leda Schum., senso stricto, 1817. Type L. rostrata Mtg. Shell elongate, rostrate, with conspicuous concentric sculpture, slightly gaping at the rostral end. B. Lembulus (Risso em.) Fischer, 1886. Type L. fella (L.) = L. Rossianus Risso. Shell shorter, with radial ribs on the rostrum, and oblique sculpture not wholly coinciding with the incremental lines. Ex, LZ. celata Cont. (not Hinds), Eocene. C. Jupiteria Bellardi, 1875. Type L. concava Bronn. Shell short, arcuate, inflated, sharply pointed behind the valves, not gaping, sculpture concentric or faint, without radial ribbing, usually small sized. is) TRANSACTIONS OF WAGNER 580 TERTIARY FAUNA OF FLORIDA c. Ledella Verrill, 1897 (= Junonia Seguenza, 1876, not of Hiibner). Type L. messanensis Seguenza. Differs from /upiterta by having a straighter rostrum, with the margin retuse below it. These differences disappear in a large series of species, and the transition between slightly rostrate forms and those with rounded posterior extremity is complete. Leda pontonia Dall, is a typical, but unusually large, /wpiteria. cc. Ledina Dall. Type L. eborea Conr., 1860, not 1846, = L.. smirna Dall, Eocene. Shell solid, strong, arcuate below, both ends evenly rounded, valves nearly equilateral, smooth. This section has been frequently placed with Volda. D. Perrisonota Conrad, 1869. Type L. protexta Conr., Eocene. Shell elongate, smooth, compressed, inequilateral, with valves closed in front, the rostrum very long, not ribbed, and slightly gaping at the end. The recent ZL. Carpentert and L. extenuata Dall belong to this group. BE. Adrana H. and A. Adams, 1858. Type L. elongata Sby., recent. Very elongate and thin, flattish, subequilateral, gaping at both ends. This group, as far as the shell is concerned, approaches very near some Yoldias, but on the other hand a complete series of species (such as L. Guppyi Dall, Oligocene, Trinidad) connect it by easy stages with typical Leda. It should be borne in mind that the length and attenuation of the rostrum is not necessarily correlated with the length of the siphons, for many species with an extremely long rostrum have a very small and shallow pallial sinus; while others which are not rostrate at all (ex. Voldia scapania Dall) have a large and deep sinus. The correlation is probably with the mantle lobes, which in the Waculacea generally are apt to be peculiarly modified and often exhibit special appendages. While the typical members of the groups above alluded to seem quite distinct from one another, large series of species may be relied upon to bridge any of the indicated gaps. The principal stress in the classification of the /Vaculacea has been placed on the position of the ligament and resilium, after the grand division into pearly Muculide, without siphons, and porcellanous Ledide, with siphons, had been made. FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA Isat (ee) = It is observable that the ascent of the ligament and the obsolescence of the resilium has taken place in shells of all types; so that, in the subfamily Malletine, related most nearly to the Ledas by the porcellanous constitution of the shell, we have Lediform, Yoldiform, and even Nuculiform types. It is also notable that the external ligament is sometimes amphidetic, and in some other cases, when functionally opisthodetic, is so supplemented by a continua- tion forward of the periostracum as to appear amphidetic. In Malletia proper there is a tendency for the edge of the hinge-plate to turn up so as to form an anterior lateral tooth of a feeble kind which corresponds to a groove in the hinge-plate of the opposite valve, while in Plewrodon (or Nuculina) the anterior lateral is fully formed and conspicuous. In several forms in which there is no internal resilium in any stages yet observed, there is a vacant triangular area between the anterior and posterior ranks of teeth which corresponds to the area occupied by the chondrophore in Zeda and YVoldia, and which, if not observed with great care, might easily be mistaken in a fossil for a functional chondrophore. Subfamily MALLETIN 2. The groups included in this subfamily are as follows: Genus MALLETIA Desmoulins, 1832. (+ Solenella Sby., 1832, + Ctenoconcha Gray, 1840.) Type MZ. Norrisu (Sby.) = chilensis Desm. Shell yoldiform, with external opisthodetic ligament amphidetically ex- tended by periostracum and resilium, but neither lunule nor escutcheon, the anterior tooth row short and the rostrum obsolete. Psewdomalletia Fischer is synonymous, fide Verrill. Subgenus? NEILO A. Adams, 1852. Type WV. australis Quoy and Gaim. (+ WV. Cumingu Ads.). Shell like Portlandia, the anterior and posterior teeth more nearly equal in number. N. gigantea Smith from Kerguelen is intermediate between this group and Malletia proper, both in amount of rostration and number of hinge-teeth. M. obtusa Sars, the type of Pseudomalletia, has absolutely no trace of rostrum, though, according to Sars, it has at least one long siphonal tube. Genus TINDARIA Bellardi, 1875. Type TZ: arata Bellardi; Pliocene of Italy. TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA 582 Shell solid, closed, concentrically sculptured; ligament and resilium amphi- detic, outside the hinge-plate or line of teeth; mantle open below, with an anal orifice above, but no tubular siphon; pallial line feebly waved or entire. Sections : a. Tindaria s. s. Shell veneriform, not rostrate ; ligament elongate, feeble, mostly posterior; resilium obsolete; pallial line not sinuated. Ex. 7: cytherea and amabilis Dall, T. callistiformis V. and B., T. virens, and T. smithii Dall (++ cuneata Smith). b. Tindariopsis V. and B., 1897. (Type T. agathida Dall.) Shell more acute or even rostrate behind; ligament long; resilium short, central, in a socket or excavation above the tooth-line; pallial line feebly waved. Ex. 7: acinula and T. @olata Dall. This section is probably to be consolidated with the next. c. Neilonella Dall, 1881 (-- Saturnia Seguenza, 1876, non Schrank, 1802). Differs from Tindariopsis only in having a gap in the line of the teeth, dividing them into anterior and posterior series, through which the resilium, though above the tooth-line, can be seen from below. The type NV. corpulenta Dall is attenuated behind but not distinctly rostrate, and the pallial sinus is a little more marked than in 7: agathida. T. pusio Phil., Seguenza’s type, is distinctly rostrate, and on a casual glance hardly to be distinguished from 7, agathida. None of the Tindarias have an absolutely unbroken arch of teeth, though between the proximal ends of the two series there is often no empty space, yet the series are always distinguishable. d. Pseudoglomus Dall. Type Voldia pompholyx Dall. Shell smooth, closed, thin, minute, subcircular, with the ligament short, a little sunken, but visible only externally; the teeth few, in equal series, separated by a short, empty gap; pallial line simple. This shell has the form of Glomus, but no internal resilium, It differs - from the rounded Ledas described by Jeffreys, such as sericea, expansa, and subequilatera, by the non-interruption of the tooth-line by the base of the ligament, and from Zindaria proper by its orbicular shape, thin shell, and smooth exterior. If it were worth while to name all the stages in the very uniformly pro- gressive series which connects the typical Leda with Tindaria, Malletia, etc., no doubt this list of sections might be largely extended. FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA Q) 583 In his interesting review of the genera of Ledide and Nuculide of the Atlantic coast of the United States (Am. Journ. Sci., Jan., 1897, pp. 51-63) Professor Verrill, in his remarks on his subfamily Z2xdarune@ (page 58), ob- serves that the writer has proposed the family Ctenodontid@ to include the ex- tinct genera Paleoneilo, Nuculites, and others, but that it is doubtful “ whether Ctenodonta itself belongs here.” He also cites “ Ctenodontide Dall, pars” as synonymous with his subfamily Zizdarin@. All this expresses a complete misconception of the arrangement made by me (pp. 515-516). None of the members of Z2zdarune, Verrill, are comprised in the group suggested doubt- fully by me as “? Family Crenxodontide,” and I did not mention Paleoneilo, but expressly stated that “many forms” “described under the name of Ctenodonta” “belong in the MWuculide or Ledide,’ and placed all the members of Pro- fessor Verrill’s Zimdarung, as he does, under the Ledide. I had not the slightest intention of combining Zzzdaria and its allies with Ctenodonta, but indicated their separation as complete. Czeodonta has been referred to Arcide by Zittel and several of the older authors, but the indications all point to the derivation of the very modern group of Arc7d@ through the Pec- tunculoid Taxodonts at a much later period than the appearance of Crtenodonta, Not having a proper series of specimens of the older forms, I have preferred to avoid attempting a revision of the Paleozoic genera, which comprise the beginnings of so many different groups, and require for adequate comprehen- sion a truly monographic treatment. Subfamily SAREPTINZ A. Adams. Nuculacea with a more or less developed external ligament in addition to a sunken or internal resilium, a short hinge-plate, a simple pallial line, and a porcellanous shell. The species are usually small and rounded, smooth or concentrically striated externally, not rostrate, and without crenulations on the margins of the valves. Genus SAREPTA A. Adams, 1860. Shell rounded-ovate, with a feeble remnant of an external ligament above and at the end of the elongated narrow oblique resilium, which latter is seated on a wider triangular area of hinge-plate interrupting the short series of oblique attenuated teeth; valves closing completely. Type S. sfe- ciosa A. Adams, Japan. é While the resilium is still within the area usually occupied by a chon- TRANSACTIONS OF WAGNER 584 = TERTIARY FAUNA OF FLORIDA drophore, it is elongated and narrow, indicating a first step towards the con- dition found in the next genus. The teeth are elongated on one side of the 4. and shortened on the other, making the two limbs very disproportionate. There is no modification of the edge of the hinge-plate simulating a lateral lamina, as in Pledrodon. Genus GLOMUS Jeffreys, 1876. Shell rounded, the resilium larger and much extended below the teeth posteriorly, the extended chondrophores nymph-like, the limbs of the A- shaped teeth still more unequal, otherwise like Sarepfa, the ligament per- ceptible. Type G. zztfens Jeffreys, Proc. Roy. Soc., June, 1876. Genus MICROYOLDIA Verrill, 1897. Shell veneriform, closed, with a distinct external ligament and a strong internal resilium situated on the hinge-plate and not overrun by the posterior line of teeth; teeth few and short, less unequal-sided than in G/omus or Sarepta. Type JZ regularis Verrill. In the structure of the shell, according to Professor Verrill’s figures, this genus differs from Glomus only in minor details. The inequality in the sides of the angulated teeth seen in the above- mentioned forms, and also in some species of Leda (ex. L. extenuata Dall), is carried to its greatest extreme in a small Leda-like shell named Sz/cula fragilis by Jeffreys (1879), where the teeth are reduced to long, imbricated laminze, in which the usual hook at the proximal end is missing. In its other characters Sz/zcula hardly differs from some Yoldias, I have included these forms to complete the synopsis of the more modern groups, and also because some of them are represented on our Atlantic coast and may be expected eventually to turn up in our Tertiary beds. Leda protexta Gabb. While considering matters of nomenclature it seems desirable to clear up a confusion of long standing involving the specific name of profexta in this genus. Several persons have attempted to do this, and each seems to have left a little added confusion of his own, while throwing some light on the subject. In March, 1860, in the Journal of the Academy of Natural Sciences, 2d Ser., iv., p. 303, Gabb described a Leda protexta from the New Jersey Cretaceous FREE INSTITUTE OF SCIENCE 585 TERTIARY FAUNA OF FLORIDA S marls. By some misfortune nearly all the figures on this plate are numbered discrepantly with the text. The figure of this species is No. 23 on the plate, as can be determined by comparing the description with the figure. On page 397 of the same volume, published in November of the same year, Gabb refers to the same species, describes and figures* (pl. 68, fig. 36) a Leda from the Ripley group of Hardeman County, Tennessee, which is undoubtedly distinct from his original protexta of New Jersey. Not content with this, in 1864 (Pal. Cal., i., p. 199, pl. 26, f. 185) he refers a third species of Leda from the Cretaceous of California to the New Jersey species of 1860. In 1865 Conrad described (Am. Journ. Conch., i., p. 213, pl. 21, fig. 2) a cast of a Leda, distinct from any of the preceding, under the name of Yoldia protexta, from the Eocene of Shark River, New Jersey. In 1866 (Smithsonian Checklist, Inv. Foss. N. Am., Eocene and Oligo- cene, pp. 3, 4) Conrad catalogues a Muculana Gabbi from California without comment, which Gabb (Pal. Cal., ii., pp. 197, 250, 1869) states is a new name proposed for Leda protexta Gabb of California, 1864. In the same Checklist Conrad (p. 4, No. 55) enumerates a Nuculana pro- texta Conrad from Alabama of which nothing had previously been printed, as well as his ‘‘ Yoldia” (= Leda) protexta of New Jersey (p. 4, No. 65). The latter is correctly referred by Conrad to his genus Mucwlana (= Leda) in his catalogue of the Eocene Testacea of the United States (Am. Journ. Conch., i, p. 13, Feb., 1865); and still later (Am. Journ. Conch., iii, p. 8, Apr., 1867) he corrects the synonymy of this species by renaming it a/darza, and transfers it back to Yo/da, the wrong genus. In 1869 Conrad (Am. Journ. Conch., v., p. 98, pl. 9, fig. 24) describes as a new genus ferrisonota, the internal cast of another Leda, which he called Perrisonota protexta. Thus, in spite of the elimination of two species of this specific name, there still remained three species, Gabb’s Nos. 1 and 2 and Conrad’s last, all called protexta / In 1885 Professor R. P. Whitfield (Brach. and Lam. of the Raritan Clays of N. Jersey) took up the subject. For the first Leda protexta of Gabb he adopts the name Muculana protexta, and gives a new description (p. 105, pl. xi., fig. 10) and a figure of the specimen from which it is supposed Gabb’s original figure of ZL. protexta was made. For Gabb’s second proterta Whitfield proposes the name Gadéana, and in illustration of it gives figures of a cast * The figure mentioned in the text is 35, but the number on the plate is 36. TRANSACTIONS OF WAGNER 586 TERTIARY FAUNA OF FLORIDA from Princeton College obtained from the marls of Freehold, N. J. (of. cét., p- 108, pl. xi., figs. 12, 13), which he supposes to be identical with the Ten- nessee species, and also of a smaller specimen which should, from the figure, belong to another and distinct species. The Tennessee shell must, of course, keep the name, being the original type. This has been redescribed and figured (Bull. Am. Pal., iv., p. 55, pl. iv., fig. 9, 1896) by Harris, to whom Professor Safford lent the type specimen, which really came from the Midway Eocene and not from the Cretaceous Ripley beds as now restricted. Professor Harris apparently overlooked the name given by Whitfield and renamed the species L. Saffordana. In this connection it may be pointed out that the two casts figured by Professor Whitfield as illustrative of Conrad’s L. albaria (op. cit., p. 228, pl. xi., figs..15 and 16) cannot, in my opinion, be regarded either as belonging to one and the same species themselves, nor can either of them be referred to Conrad’s original species. As they cannot be specifically iden- tified without better material it is best not to name them. In the synonymy of VY. protexta Conr. (= albaria) Professor Whitfield remarks “not Voldia pro- texta Gabb,” but this should read “ not Leda protexta Gabb,” since I believe Mr. Gabb did not describe a Yo/dia with that specific name, though he gave the latter to three different species of Leda. Lastly, Professor Harris, in his synonymy, queries whether the Leda bella var. Conr., from Alabama, may not be identical with Z. Gabbana. It is possible that this may be the shell meant by Conrad in his Eocene Checklist when he catalogued a Wuciulana protexta from Alabama, as above mentioned. But, since it is absolutely impossible to determine the question either way, it will not be profitable to discuss it. The lesson taught by this whole chapter of blunders is sufficiently obvious. Leda acala n. s. PLATE 32, FIGURE 3. Wood's Bluff, Alabama, C. W. Johnson; Butler, Alabama, Aldrich. Shell thin, nearly smooth, elongate, acutely rostrate, inequilateral, moderately convex; beaks small, prominent, but not high; anterior slope shorter, slightly descending; anterior end rounded; posterior slope nearly straight, posterior end narrow, bluntly pointed, base arcuate; lunule very narrow, almost linear, slightly raised, the incremental lines near it strong; escutcheon narrow, excavated, bordered by a sharp elevated line, outside of FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA 587 which is a wider furrow extending to the upper end of the rostrum ; interior smooth ; pallial sinus angular, well-marked; seventeen anterior and eighteen posterior teeth, which are small and delicate; chondrophore subumbonal, not projecting. Lon. 18, alt. 8, diam. 5.5 mm. This species and another were in the hands of Mr. T. H. Aldrich when he described his Leda clongatoidea (Bull. Am. Pal., No. 2, p. 17, pl. v., fig. 2). His description and figure apply to that one, and his remark about larger specimens to the present species. From the types ZL. clongatoidea is a smaller and flatter species with a sculptured ray on the rostrum and stronger incre- mental lines. The same species has been found in the Zeuglodon bed of Alabama. Leda pharcida n. s. PLATE 32, Ficure 8. Lignitic or Chickasawan Eocene of Wood’s Bluff, Alabama, C. W. Johnson and T. H. Aldrich; also at McKay’s marl bed, Suwashee Creek, two miles south of Meridian, Mississippi, L. C. Johnson. Shell solid, large, elongated, sharply sculptured; anterior end shorter, posterior end longer, rostrate, obliquely truncate; surface covered with low, sharp, concentric, elevated laminz with slightly wider interspaces, ending above anteriorly on the lunular carina, behind angulated at the lower border of the rostral ray, the interspaces much wider on the ray, and the lamine strong and blunt on the dorsal edge or keel of the ray; beaks inconspicuous ; lunule nearly linear, slightly excavated; escutcheon deep, flat, with an elevated line, inside of which are longitudinal and outside of which are oblique striz; end of the rostrum obliquely truncate, slightly recurved; base arcuate ; pallial sinus rounded, small; there are more than thirty-five teeth on each side of the moderately large subumbonal chondrophoric pit; the rostrum has no internal ridge. Lon. 36.5, alt. 14, diam. 7 mm. This is nearest L. opulenta Conr., in which the sculpture of the rostral ray is divided into two areas of loops by a sharp groove, and the escutcheon is much smoother and divided into deeply excavated areas. This species is sometimes found in collections under the name of ZL. frotexta Conrad, but there is no evidence of any connection specifically between them or any of the synonymes of protexta. L. opulenta isa much rarer shell from the Clai- bornian. ZL. regina-jacksonis Harris (Jacksonian) is higher behind, with the middle ventral margin straight, and feebler sculpture. TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA 588 Leda multilineata Conrad. PLATE 25, FIGURES II, 114. Leda multilineata Conr., Proc. Acad. Nat. Sci. Phila., vii., p. 258, 1855; Wailes, Geol. Miss., p. 289, xiv., fig. 4 (bad), 1854. Eocene: Moody’s branch beds, Jackson, Mississippi; Wahtubbee Hills, Clarke County, Mississippi; near Hickory; four and a half miles east of Shu- buta, eight miles west of Enterprise, and six miles west of De Soto; Oligocene: Vicksburg limestone, Mississippi, Burns ; nummiulitic beds near Martin Station, Florida, Willcox. Length of figured shell 20 mm. This fine species, which appears to range from the Middle Eocene to the top of the Lower Oligocene, has not hitherto been well figured, for which reason I have given an illustration of it. Leda concentrica Say. Nucula concentrica Say, Journ. Acad. Nat. Sci. Phila., ist Ser., iv., p. 141-42, 1824 ; not of Fischer, Fos. Gouv. Moscow, 1843. Leda eborea Conr., Proc. Acad. Nat. Sci. Phila., xiv., p. 1846; zbzd. for 1863, p. 581; not ZL. eborea Conr., Journ. Acad. Nat. Sci. Phila., 2d Ser., iv., p. 295, pl. 47, fig. 26 (= L. smirna Dall). Upper Miocene of Alabama, of the Deep Well at Galveston, Texas (four hundred and forty to four hundred and fifty-eight feet below the surface), Pleistocene of the Gulf Coast, and recent in the Gulf of Mexico; Say, Harris, Mitchell, Dall, and others. Leda catasarea n. s. PLATE 32, FIGURE 13. Eocene of the Wahtubbee Hills, Clarke County, Mississippi, at stations 2616, 2621, 2622, 2624, and 2625; Burns. Shell small, very plump, nearly equilateral, concentrically sculptured, with on the beaks and body rather wide, flattish riblets, more crowded ventrally, obsolete dorsally behind and on the dorsal and anterior portions in front; lunule very narrow, excavated, with the valve margins slightly pouting ; the escutcheon similar, wider, with an excavated, obliquely grooved furrow out- side of it, with rounded outer edges, the whole forming a conspicuous lanceo- late area extending from the point of the rostrum to the beaks; anterior end of shell rounded, base arcuate, posterior end with a short, bluntly pointed rostrum; hinge solid, with about sixteen anterior and fourteen posterior V- FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA 589 shaped teeth; chondrophore small, subumbonal; the rostrum without an internal ridge, the pallial sinus small. Lon. 5.2, alt. 3, diam. 2.5 mm. This interesting little species appears to be rather common in beds of the Wahtubbee horizon. It differs from ZL. robusta Aldrich in details of sculpture, especially on the escutcheon. Leda flexuosa Heilprin. PLATE 38, FIGURES 5, 5 a. Leda flexuosa Heilprin, Trans. Wagner Inst., 1., p. 119, pl. 16, fig. 66, two views, 1887. Oligocene silex beds of Ballast Point, Tampa Bay, Florida; . Heilprin and Dall. This species was imperfectly represented by the original figures, and at the suggestion of Mr. Willcox new figures of it have been included here. Leda hypsoma na. s. PLATE 32, FIGURE 2. Miocene of the Natural Well, Duplin County, North Carolina; Burns. Shell small, polished, compressed, with the rostrum short, pointed, and gaping at the end; sculpture of fiattened, wide, concentric waves or riblets, with their dorsal slope steeper; these waves are obsolete over the anterior dorsal and terminal part of the valves, and wholly absent from the rostrum; beaks nearly central, plump, low; lunule very narrow, bordered by an im- pressed line; escutcheon wider, bordered by a large, rounded rib on each side, the area longitudinally grooved; rostrum slightly recurved; base arcuate; interior polished, with a small pelts sinus ; fourteen anterior and about eleven posterior teeth; the chondrophore minute, subumbonal; the rostral channel not divided by a ridge. Lon. 5.5, alt. 3.2, diam. 1.5 mm. This species recalls Muculana linifera Conr., but is larger and more elongated, with a more conspicuous rostrum. Leda dodona n. s. PLATE 32, FIGURE 6. Oligocene of the Oak Grove sands, Santa Rosa County, Florida; Burns. Shell small, solid, slightly inequilateral, polished, strongly concentrically sculptured; sculpture of elegant, even, high, blunt-edged, slightly recurved lamella, with deeply excavated, wider interspaces, which are striated by the lines of growth; the sculpture ends anteriorly at the margin of the lunule, TRANSACTIONS OF WAGNER 599 TERTIARY FAUNA OF FLORIDA and behind ceases on the rostral carina, about equally strong throughout; a radial depression extends from the beak to the anterior ventral margin, which it slightly emarginates ; lunule narrow, transversely ribbed; escutcheon wider, extending to the end of the rostrum, bounded by a strong, rounded carina, on which the lamellae are conspicuous; within the carina the area is excavated and nearly smooth, except in the central part, where it is radially grooved; rostrum acute, slightly recurved near the tip, pallial sinus small; hinge with nineteen anterior and fourteen posterior rather solid teeth; chondrophore small, triangular. Lon. 9, alt. 5, diam. 4 mm. This elegantly sculptured species is related to L. robusta Aldr., L. besulcata Guppy, Z. acuta Conrad, etc., but in the minor details of its sculpture. differs from all of them. Leda trochilia n. s. PLATE 32, FIGURES 4, 12. Miocene of the upper bed at Alum Bluff, Calhoun County, Florida; Dall and Burns. y Shell small, solid, nearly equilateral ; sculpture of concentric riblets, not always continuous, with wider interspaces; the ribs when continuous extend forward to the margin of the shell; there is no lunule, or its area is barely indicated by a feebly impressed line which does not interrupt the sculpture; there is a very feeble anterior depressed ray which does not emarginate the base; anterior end rounded, shorter; base arcuate, posterior end rostrate, pointed ; the escutcheon is almost as in the last species, but its carina bears no lamellz, as the concentric sculpture is little elevated and only in certain specimens crenulates the carinze; interior much as in ZL. dodona with the same number of stout teeth (sixteen) before and behind the small triangular chondrophore. Lon. 10, alt. 6, diam. 4 mm. This is another species of the same group as L. dodona, but with coarser and less regular sculpture and obsolete lunule. Leda acrybia n. s. Chesapeake Miocene of Plum Point, Maryland; Burns. Shell resembling Z. ¢rochilia, but thinner and more compressed, with a wider rostrum, which is nearly smooth and slightly recurved; the young are hardly rostrate; there is a narrow lunule and escutcheon, the latter subdivided by an oblique ridge and nearly smooth; there are sixteen teeth on each side of a small chondrophore. Lon. 10, alt. 5, diam. 3.75 mm. FREE INSTITUTE OF SCIENCE I TERTIARY FAUNA OF FLORIDA 59 The material for this species is sparse, and I await better specimens for figuring, but there is enough to indicate clearly that the species is distinct from any of those compared with it. Leda (linifera Conrad, var. ?) canonica n. s. ? Cf. Leda lintfera Conr., Am. Jour. Conch., 1., p. 139, pl. x., fig. 8, 1865. Jacksonian of Garland’s Creek, Clarke County, Mississippi, Spillman ; the variety from the Oligocene marl of Chipola River, Calhoun County, Florida, Dall. The shallow radial furrow on. the rostral end of Conrad’s shell is misrep- resented as a rib on his figure. The shell is subrhomboidal and compressed with the concentric lines sparse, obsolete anteriorly and on the rostrum. The present form, represented by two small specimens about 2.5 millimetres long, is more elongate, less compressed, the rostrum has a rounded dorsal keel, and the surface is uniformly covered with fine, even, concentric sculpture. It is probably a distinct species, less robust than young Z. acuta Conr. of the same size, but for which the material is hardly adequate to a full description and figure. The shell is near ZL. calatabianensis Seguenza (Nuc. terz., pl. ii., fig. 9 @) from the Astian of Italy. The Chipola beds have afforded another species of the same group (Nat. Mus. 114,808) which in form and sculpture much resembles ZL. /énzfera, but the shell is more inflated, the rostrum more pointed, with a marked inflection of the basal margin below it, and the anterior end is more attenuated. For the present this may take the provisional name of L. “ifera var. chipolana, though sufficient material would probably show it to be distinct. It is repre- sented in the collection by only a single specimen 2.5 millimetres long. Leda amydra n. s. ? A single valve from one mile south of Plum Point, Maryland, was collected in the Miocene by Harris. Shell small, smooth, polished, subequilateral, moderately convex, with an evenly arcuate base, no lunule, and the escutcheon small, narrow, exca- vated, bounded outside by a raised line beyond which is a second furrow ex- tending nearly to the end of the rostrum; the chondrophore is small and deep-seated with about a dozen small teeth on each side of it; the rostrum is short, rounded, and without any internal partition. Lon. 5, alt. 2.5, diam. 1.5 mm. TRANSACTIONS OF WAGNER 592 TERTIARY FAUNA OF FLORIDA This shell is remarkably like a small Zeda from the Claiborne sands which I have without a name, but is more rounded behind. More material is needed to establish its exact relations. Another valve was found at Plum Point which may be distinct, or possibly a variety of this species, from which it differs by its thinner shell and by having fine concentric sculpture on and near the beaks and on the anterior dorsal slope. Leda phalacra n. s.? Miocene of Plum Point, Maryland; Burns. This shell, also represented by a single valve, is less arcuate and more compressed than L. amydra,; the middle third of the convexity of the shell has a few conspicuous concentric waves which do not reach the base and end abruptly before and behind; the beaks are covered with concentric sculpture, which also appears on the anterior dorsal slope; there is a well-marked narrow, impressed lunule and escutcheon, but the hinge, though feeble, resem- bles that of Z. amydra. Lon. 5.5, alt. 2.7 mm. These little Yoldiform Ledas would be easily mistaken for Yoldias; and, in fact, many have been so referred by authors, but sufficient study will enable almost any of them to be properly referred. While the distinctions are chiefly anatomical, the solidity of the shell, the presence of a rostral ray, a lunule, and concentric or radial sculpture are all characteristic of Leda and not of Yo/dia, and some of these characters are almost always present, and taken with the general habit of the shells are sufficient to distinguish them. I may add that I have fragments of a beautiful Adrana from the Pliocene of Limon, Costa Rica, but prefer to await better specimens before attempting to name it. Leda acuta Conrad. Nucula acuta Conrad, Am. Mar. Conch., p. 32, pl. vi., fig. 1, 1831 ; not of Sby., Trans. Geol. Soc. Lond., 2d Ser., v., pl. 39, fig. 5, 1837. Leda cuneata Sby., P. Z. S., 1832, p..198. Leda jamaicensis Orb., Moll. Cuba, i., p. 262, pl. xxvi., figs. 27-29, 1846; Dall, Bull. Mus. Comp. Zool., ix., p. 124, 1881. Leda unca Gld., Proc. Bost. Soc. Nat. Hist., viii., p. 282, 1862; Verrill, Trans. Conn. Acad., v., p. 572, 1882; not vi., p. 260, 1884. Leda inornata A. Ads., fide Hanley, from type. Leda acuta (Conrad) Dall, Bull. Mus. Comp. Zool., xii., p. 251, 1886; xvili., p. 438, 1889. FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA 593 Oligocene of the Chipola beds, Calhoun County, Florida, Dall and Burns, and of the Alum Bluff beds at Oak Grove, Santa Rosa County, Florida, Burns. Miocene of Suffolk and Yorktown, Virginia; of Wilmington, North Carolina, of the Natural Well, Duplin County, North Carolina, and of Dar- lington, South Carolina; Burns and Harris. Pliocene of the Dismal Swamp, Virginia; of the Waccamaw beds, South Carolina; of the Caloosahatchie beds, Florida, on the Caloosahatchie, Alligator Creek, and Shell Creek; John- son, Burns, Dall, and Willcox. Recent in thirty to one hundred and fifty-five fathoms on the southeast coast of the United States and in the Antilles and on the Pacific coast of California. This widely distributed and ancient species is represented in the Oligo- cene of Bowden, Jamaica, by L. d¢sz/cata Guppy (non Whitfield). Like some other species of the sub-genus Lemdulus it is subject to a wide range of variation in its external sculpture. This may be finely and regularly con- centric over the whole surface, or partly obsolete towards the ends and base. Occasional specimens are found in which the surface is nearly smooth and others in which the fine concentric ribbing is replaced by a few distant, coarse ribs or waves. In fact, the extremes are so discrepant that in the absence of a connecting series almost any one would doubt that the shells could belong to one and the same species. ZL. robusta Aldrich varies in a similar manner. Other species of the same group, such as ZL. ¢aphria Dall (ce/ata Hinds, non Conrad) and ZL. feltella Dall, even when gathered in large numbers, show a eratifying uniformity of character. Hence it follows that much caution should be used in naming new forms from beds where named species of this group are already known to occur. Genus YOLDIA Moller. This group appears to be, on the whole, more modern than the typical Leda, and occurs for the most part rather sparingly in the Tertiary. Though the number of species is small, individuals are astonishingly numerous in some localities, and one stratum at Shell Bluff on the Savannah River is almost entirely composed of the fossilized valves of a single species of Volda. After eliminating the Yoldiform species of Leda, comparatively few species remain to be discussed. YVoldia glactahs Wood, described from recent speci- mens, was described from the Pleistocene of New England as Y. portlandica Hitchcock, and is the Y. arctica of several authors, but not of Gray. YVoldia TRANSACTIONS OF WAGNER 594 TERTIARY FAUNA OF FLORIDA albaria Conrad, from the New Jersey marls, was originally named frofexrta, and belongs to the genus Leda (g. v.). . Yoldia Coopert Gabb, a fine species, erroneously referred afterwards to Y. zwzpressa Conrad, is found recent and in the later Tertiaries of California. Y. z#zpressa Conrad was described from the Eocene of Oregon. Y. /evis Say, which has been confused with its probable descendant VY. “imatula Say, is abundant in the Miocene of the eastern United States. VY. abrupta Conrad (1848, not of Dana, 1847) is an obscure species from the Oregon Tertiary. Y. xaswta and ovalis Gabb were described from the Oligocene of St. Domingo. The earliest Tertiary species I have noted from our own country is Y. Azzdle: Harr., from the Midway Eocene of Ten- nessee. YVo/dia eborea (Conrad) Harris is a Leda, but judging from the figure (Bull. Amer. Pal., iv., pl. 4, fig. 10), the species doubtfully referred to Leda elongatoidea Aldr. by Professor Harris, and which he has since named YVolda Aldrichiana, belongs to the genus Voldia. From the Claibornian we have the rare VY. claibornensis Conrad; from the Oligocene of the Antilles Y. Croshyana Guppy; Y. ser?ca Conrad is a good species from Red Bluff; and Shell Bluff, Georgia, and the Floridian Chipola beds have a species apiece. Y. corpu- lentoidea Aldr., with eborea Conrad and similar forms, are better placed in the genus Leda. This genus has been variously subdivided, especially in Professor Verrill’s paper above alluded to, but a conservative view, taking into account the variable characters exhibited by the respective species and the indubitably close relations with Leda, obliges me to withhold from the most marked of the several groups a more than sectional value, and to regard a large pro- portion of the names as synonymes. _ The following arrangement, based on the above considerations, may, perhaps, be accepted. Genus YOLDIA Moller, 1842. Two species were referred by Moller to his new genus, one of which was, according to Morch, Y. glactalis Wood (=V. “ arctica Gray,’ Moller), and the other a young specimen of Y. éhracweformis Storer (= Y. angularis Moller). The original Macala arctica Gray is indeterminable from the brief diagnosis, and was not figured. It has been identified by several naturalists (Hanley, Smith, and others) with V. Ayperborea Torell, and by others with VY. glacialis Wood (+ VY. #uncata Brown, + Y. portlandica Hitchcock). From Moller’s ‘ description of his VY. arctica as ‘“planiuscula, levi, nitida, luteo-vel fusco i 5) J ) FREE INSTITUTE OF SCIENCE : : 595 TERTIARY FAUNA OF FLORIDA virente,’ and the number of teeth he ascribes to it, I feel compelled to believe that it could not have been Y. g/acialis, whatever Gray's NV. arctica was.* Sections : A. Voldias.s. Type Y. hyperborca (Loven MS.) Torell. Shell elongate, smooth, compressed, more or less pointed behind, having a deep pallial sinus and with a wide pedal and moderate si- phonal gape. Ex. Y. /evis Say, Miocene, Virginia. B. Cnesterium Dall. Type VY. arctica Brod. and Sby., Zool. Journ., 1829; (not of Gray, Parry’s Voy. App., 1824) = V. scassurata Dall. Shell like Voda with incised sculpture not in harmony with the incre- mental lines over more or less of the external surface. Ex. Y. lancco- lata J. Sby., Pliocene. C. Orthoyoldia Verrill. Type Y. scapina Dall. Shell smooth, without rostrum or carina, the ends bluntly rounded. Eocene, recent. D. Voldiclla Verrill. Type Y. lucida Loven. Shell small, rounded ovate, smooth, with obscure rostration feebly developed, with a small or indistinct pallial sinus; resilium well devel- oped, short, sometimes partly visible externally. These are mostly small deep-sea forms, of rather generalized character, which verge on Woe//etia in their ligamental features, and are very much like the young of some of the larger forms. Professor Verrill ascribes to them a feeble external ligament, but it seems to me more like the continuous peri- ostracum which is visible in a fresh specimen of V. ¢hracieformis, and which has no real ligamentary function. The dorsal valve margins do not entirely close over the resilium, though its attachments appear to be wholly internal. E. Portlandia Morch. Type V. glacialis Wood (+ V. portlandica Hitchcock, Pleistocene and recent. Megayoldia Verrill). Shell convex, more or less abruptly truncate behind, the rostral part laterally compressed ; the pallial line with a deep sinus. The gaping of the valves in Y. thraczeformis is merely a specific character and varies in the same species and in different ages of the same individual. * In this also I agree with Hanley and Smith in referring Gray’s species to the hyferborea group rather than to that of ¢rwmcata Brown, as supposed by Torell, Jeffreys, and Mérch. Yoldia arctica Brod. and Sby. (1829) is a totally distinct species, which I have named Y. scésswrata. 3} TRANSACTIONS OF WAGNER 596 TERTIARY FAUNA OF FLORIDA Y. montereyensis Dall, otherwise very close to Y. thracteformis, does not gape perceptibly more than Y. g/acialis. The soft parts of V. thracieformis differ in no essential respect from those of Portlandia glacialis. 1 cannot regard - the differences of any of the above forms as of more than sectional value. They all intergrade in a large series of species. Yoldia leevis Say. Nucula levis Say, Journ. Acad. Nat. Sci. Phila., 1st Ser., iv., p. 141, pl. x., fig. 5, 1824. Miocene of Maryland (Say); St. Mary’s County, Maryland; York River, Virginia; Warwick and Dismal Swamps, Virginia; Burns, Harris, Haldeman, etc. This species is probably the ancestor of the Pleistocene and recent Y. limatula Say. It differs from the latter by its proportionally larger chon- drophores, smaller and more numerous teeth, somewhat more pointed pos- terior end, and less compressed escutcheon. A very large series compared shows these differences to be constant. Yoldia psammoteea n. s. PLATE 34, FIGURE 20. Claiborne sands, at Claiborne, Alabama; Burns. Shell smooth, or with faint incremental lines, inequilateral with low beaks, the dorsal and ventral margins subparallel; valves elongated, rounded in front and behind, the posterior part somewhat compressed and attenuated ; anterior end with a moderate gape; lunule and escutcheon elongated, very narrow, almost linear. Lon. 21, alt. 9, diam. 6 mm. This species is represented by two specimens with the valves closed and filled with a rather hard matrix, so that the hinge characters are inaccessible. It is clearly distinct from any of the described species of the American Eocene, and peculiar in its elongated solenoid form. It cannot be confounded with Y. clacbornensis Conrad, from the same horizon. It would find a place in the section Orthoyoldia Verrill. : Yoldia frater n. s. PLATE 32, FIGURE I. Oligocene of the Chipola beds in Calhoun and Walton Counties, Florida, Dall, Burns, and Johnson; also in the Alum Bluff sands at Oak Grove, Santa Rosa County, Florida, Burns. Shell polished, thin, elongate, much resembling Y. /evis, from which it is FREE INSTITUTE OF SCIENCE 597 TERTIARY FAUNA OF FLORIDA distinguished by the less arcuate base, more attenuated anterior end, some- what more compressed form, and, in the great majority of specimens, by having on the convexity of the beaks and the early part of their posterior slope a concentric sculpture of fine even riblets with about equal interspaces. There is also on the escutcheon an elevated radial line, absent on the corre- sponding part of VY. /evis, which also attains a nearly one-third larger size when full grown. There are about twenty-six teeth on each side of a small subumbonal chondrophore. Lon. 19, alt. 8, diam. 4 mm. This shell is perhaps the ancestor of Y. /evis, from which it can usually be readily distinguished by its ‘more rectangular form and sculptured umbones. a Yoldia tarpzeia n. s. Chesapeake Miocene of the upper bed at Alum Bluff, Calhoun County, Florida; Dall and Burns. Shell small, smooth, ovoid, moderately convex, rather solid for its size, with the ends rounded, the posterior smaller, the base evenly arcuated ; lunule very narrow ; escutcheon smooth, or marked only by lines of growth, with a single lamellose elevated line very close to the shell margin, which in young or worn specimens is often obscured; beaks low, hinge-line nearly straight, pallial sinus rounded, deep, nearly reaching the vertical of the beaks; about twenty anterior and eighteen posterior small, narrow teeth, separated by a sub- umbonal chondrophore. Lon. of a large specimen, 14.25 ; a perfect but smaller one measures, lon. 9.5, alt. 5, diam. 3 mm. : This shell recalls V. sapotl/a Gld., and bears to Y. /evzs much such a relation as Y. sapotilla does to V. Aimatula Say. Subfamily MALLETIINZA. Genus PLEURODON S. Wood. Pleurodon Wood, Charlesworth’s Mag., iv., p. 230, 1840. (lype P. ovalis Wood, of. ciz¢., p. 230, suppl. pl. xiii., fig. 1a-d.) Not Plewrodonte Fischer, Tab. Syn. Zoog., p. 129, 1808. Nuculina Orbigny, Pal. Franc., iii., p. 161, 1843. (Type Wucula miliaris Deshayes, non Wood, Coq. env. Paris, i., p. 235, pl. xxxvi., figs. 7-9, 1824.) Not Wuciwlina Agassiz or Filippi. Nucinella Wood, Crag. Moll., ii., p. 72, 1850. (LV. mzliaris Wood, non Deshayes, pl. x., figs. 4 a—c, 1850.) Deshayes, An. s. Vert. bassin de Paris, i., p. 826, 1860. Nuculina ¥. A. Smith, Challenger Pelecypods, p. 230, 1885. Verrill, Am. Journ. Sci., Jan., 1897, p. 51. TRANSACTIONS OF WAGNER 598 TERTIARY FAUNA OF FLORIDA Range: Paris Eocene; Red and Coralline Crags of Britain; Caloosa- hatchie beds, Florida; Pliocene of Reggio, Italy; recent, Straits of Florida, in two hundred and five fathoms. This very remarkable little genus combines characters which recall Nucula, Limopsts, Tindaria, and other genera, with features peculiar to itself. The history of the genus is quite complicated. _ In 1840 Searles Wood described his genus /Yeurodon, as above cited, for P. ovals of the British Crag, at the same time querying the specific identity of his type with a shell described by Deshayes in 1824 under the name of Nucula miliaris, from the Paris Basin Eocene. They were not specifically identical, though Wood in 1850 concluded that they were, and therefore enumerated his Crag species under the specific name of mzliarzs among his Crag bivalves. But since there was a genus Plewrodonte already existing, he concluded (erroneously, in my opinion) that Plewrodon was preoccupied in zoology, and substituted for it the generic name of MWzwcznella. Meanwhile d’Orbigny had observed the peculiarities of Deshayes’s species, and proposed in 1843 to make it the type of a genus Wuculina, being apparently ignorant of Wood’s Fleurodon. The word Nuculina was used by Agassiz in 1847 to include the Nacwlide in a family sense, and about 1850 Filippi, in a rare brochure, used the name Vaculina for a Cythere or allied entomostracan. The uncertainty of date common to many of d’Orbigny’s works led to doubts as to which was the prior use of the name Vuwcu/ina in a generic sense. Lastly, in 1860 Arthur Adams named an allied recent shell from Japan Hualeyia, which, being preoccupied in sponges, he replaced by Cyri//a in the same year. In 1870 a recent species of Plewrodon was found by Dr. J. G. Cooper while dredging among the islands off Santa Barbara, California. At that time I investigated the relations of these minute forms and had some correspondence about them with Dr. P. P. Carpenter and the brothers Adams. But in the absence of specimens for comparison, and doubting the minute accuracy of the published figures, my notes remained unpublished. In 1886 Dr. W. H. Rush dredged a single valve of a new species of Plewrodon in the Straits of Florida, and I discovered still another in the Pliocene marls of the Caloosa- hatchie River, Florida. With a series of the Crag shells, specimens of the species described by Deshayes, and of those from. Japan and. California, I find myself at last in a position to review the group. In 1870 I was informed by Mr. Arthur Adams that his second species of Cyrilla (C. decussata) was a young Limopsis, which eliminates that form from the discussion. » In 1885 FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA 599 Mr. E. A. Smith announced the discovery by the Challenger Expedition of P. ovalis at the Cape of Good Hope, in fifteen to twenty fathoms, at St. Simon’s Bay. I have not examined these specimens. The typical species of Plewrodon is characterized by a shell externally resembling Wacula, but having a structure much less nacreous. Mr. Wood, indeed, described his shell as nacreous, but none of the specimens given by him to Dr. Jeffreys have the least pearly lustre, and if the recent species are examined they appear hardly more nacreous than an ordinary Leda. The anterior side of the hinge-line is short, the cardinal border externally is pro- duced and angulated, and in an excavation under this little angle lies the ligament which in a normal and perfectly preserved specimen is nearly or quite covered by the margin of the valves. In most specimens this covering, being extremely thin, is eroded or broken away, so that two valves in oppo- sition show a small oval pocket in which the ligament was originally con- tained. In P. mzlaris Deshayes the perfect shell completely hides the ligament, which is wholly internal, and the British specimens indicate that this may have been the case with P. ovals also. In both of these species and in the recent P. Adamsu from Florida as well as the P. Woodi from the Caloosa- hatchie, the cavity for the ligament is rather flattish and small; in the P. munita Cpr. from California as well as the Japanese Cyri//a the cavity is large and nearly spherical. The cardinal plate in all the species is rather broad, and terminates in the left valve with a prominent lateral tooth which is received into a corresponding depression in the plate of the opposite valve, the edge of the plate in most of the species being turned up like a tooth, but in P. sunita remaining flat in the right valve. The cardinal teeth between the ligamentary fossette and the lateral tooth or socket vary in form and arrangement in each species. They are, from their minuteness and complexity, very difficult objects to observe and draw correctly. They are set in a sort of arch, under the beak, but a careful and minute study shows that the series is really composed of two dis- tinct groups, one belonging to the anterior and one to the posterior side of the hinge, and the teeth in one group are usually of a different type from those in the other group. The two rows or groups approach one another at a more or less evident angle, recalling the two groups in Nacwla,; while a reminiscence of the internal fossette of Macz/a remains in a slight broadening of the cardinal plate just below this angle. The edge in P. Woodii is actually produced into a little angular projection here, but the recent species do not TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA 600 indicate the presence of any resilium at this point, while in Cyrz//a the broad- ening of the plate has disappeared. The teeth of the anterior group in P. ovalis are bent like a half-open book standing on its base. There are three of them and they are very elevated. In position they resemble those of P. Woodid; they are thin and compressed. The posterior teeth in horizontal section are rounded, they are stouter, not so close together, not bent, and rather conical. The widening of the hinge-plate in this species is not great, and the posterior cardinal teeth rise almost directly from its inner margin. Pleurodon Woodii n. s. PLATE 24, FIGURE Io. Pliocene marls of the Caloosahatchie, Florida; Dall. Shell small, smooth, oval, slightly truncate in front, very inequilateral ; sculpture only of extremely fine incremental lines, visible only under magni- fication and stronger towards the margin; beaks small, prominent, anterior ; margins internally smooth; hinge-plate wide, extended posteriorly more than half the length of the shell, its lower edge distally turned up and thickened to form a lateral tooth, to which in the right valve is added a small dorsal thickening or lamina; anterior teeth small, three in each valve, the hinge-plate slightly angular below the commissure between the anterior and posterior cardinals ; posterior cardinals three in the right, four in the left valve, larger than the anterior teeth and separated from them by a slight gap, the hinge- plate grooved between them and its ventral margin. Lon. of shell 2.75, alt. 1.75, diam. I mm. This species differs from P. ova/s in the groove and angle of the hinge- plate, but in other respects the teeth are much alike, and the two species are closely related and of nearly the same size, P. Woodi being a trifle larger. P. miliaris Deshayes, when fully adult, is larger than the P. ovaizs and has one more posterior tooth; the anterior teeth are flatter, more compressed, and more crowded together. The young resemble the P. ovals more closely. The adults have the ligamentary fossette completely covered. The specimens were received from Dr. P. Fischer by Jeffreys. P. Reussii Deshayes, from the Tertiary of Bohemia, which was referred to P. miliaris by Reuss, I have not been able to examine. P. calabre Seguenza, from the Tortonian Miocene, I have not seen, nor do I know if it has been described and figured. The name occurs in the list of the fossils of the various Tertiary beds of Reggio in Calabria. FREE INSTITUTE OF SCIENCE 601 TERTIARY FAUNA OF FLORIDA P. Seguenze@ Dall, from the Astiano division of the Calabrian Pliocene, was sent to Dr. Jeffreys under the name of P. ovals, and I suppose is the shell so catalogued by Seguenza in his Tert. Fos. of Reggio. It is much larger even than P. mufaris, and has the ligamentary fossette somewhat gaping; eight teeth, of which five are posterior, and all are much crowded. The inner edge of the hinge-plate is excavated behind the anterior teeth, and the width of the cardinal border at the lateral teeth is less, proportionally, than in the other species. P. Adamsi Dall (plate 24, figure g) was dredged seven miles east of Fowey Rocks, Straits of Florida, by Dr. W. H. Rush. It is proportionally shorter and wider than the other species. It has three squarish high anterior cardinal teeth and two stout conical posterior teeth in the right valve, perhaps three in the other. There is a well marked small shelf between the posterior teeth and the outer cardinal border, and no groove on the other side. The exterior is smooth and covered with a pale yellowish epidermis; the interior is glassy rather than nacreous. It is figured on the same scale as P. Woodut. The posterior wing of the cardinal border is wider than in any of the other species. The reader will understand that all these notes are taken from authentic specimens and not from figures. Subgenus CYRILLA A. Adams. Huxleyia A. Adams, Ann. Mag. Nat. Hist., 3d Ser., v., p. 303, April 1860. Vype sulcata A. Adams (not “u«leyia Bowerbank). Cyrilla A. Adams, Ann. Mag. Nat. Hist., 3d Ser., v., p. 477, June, 1860; ix., p. 295, 1862. Journ. de Conchyl., xvi., p. 41, 1868. In this division of the group the fossette for the ligament has been en- larged and rounded. The space occupied by the anterior cardinal teeth in typical Pleuvodon has been so encroached upon that these teeth have been more or less absorbed or never developed, while the posterior cardinal teeth, upon which more would depend after the others were gone, have become wider and stronger and extend from the inner to the outer margin of the cardinal plate, being somewhat wedge-shaped in section or wider at the inner edge. In Cyrilla sulcata there are six cardinal teeth in the left valve. Of these, one, or possibly two, may have been originally part of the anterior series. All have been more or less modified into closer uniformity with the true posterior series; they no longer form an angle with one another, and the TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA 602 free inner edge of the cardinal plate has disappeared, so that the edge, as it now is, is close to the inner ends of the transverse teeth. The character of the lateral tooth remains much the same as in typical Plewrodon. Cyrilla munita Cpr., from thirty fathoms off Catalina Island, California, shows a further step in modification. The fossette has become still larger, none of the anterior cardinal teeth is left. The four posterior cardinals are of the bent or V-shaped variety, and the cardinal plate and shell have become more solid and heavy, though the shell is smaller than that of C: sa/cata. The ligament is still wholly internal and the cardinal plate solid and flat. The wing-like expansions of its outer margin, so notable in all the species of Plez- rodon, are gone. The character of the shell in both sections of the genus is the same, that is, glassy or Leda-like, not nacreous. In the preceding discussion of the group it will be observed that the differences exhibit a rather gradual modification from some such form as Nucula or Leda. These small shells, as in the case of the Gastropod Liote, show that the line between nacreous and non-nacreous shells is very faintly marked at times, and the difference, in such cases, cannot have much sys- tematic weight. The group in question is composed of small shells, as their relative measurements will show. Thus, in longest diameter we have Plew- rodon ovalis 1.75, P. mihtaris 3, P. Seguenze 5, P. Woodii 2.75, P. Adamsi 3.25, Cyrilla sulcata 2.25, and Cyrilla munita 2.12 mm. The corresponding shorter anteroposterior diameter is for P. ovalis 1, P. miliaris 2, P. Seguenze 4, P. Woodii 1.75, P. Adamsi 2.87, Cyrilla sulcata 1.87, and Cyridlla munita 1.75 mm. The form regarded by Mr. Smith as a variety of P. ovals Wood, in a recent state, from the Cape of Good Hope, measures 3.5 mm. high by 2.5 long and 1.75 in transverse diameter. The figure does not show the teeth with sufficient clearness to determine its relations, but knowing the great difficulty of seeing and then representing so minute and complicated a struc- ture, this is not to be wondered at. I have a doubt as to the identity of this species with the Crag fossil, but Mr. Smith’s judgment in such a matter is not to be lightly set aside. In this discussion the side of the hinge bearing the lateral teeth has been treated as posterior, thus making the ligament an- terior, as in Cuspidarza, but I am by no means satisfied that this is the correct view, and should not be surprised if it should be found necessary to reverse these terms when a living specimen shall have been examined. For those who object to the name Plewrodon on account of the existence of the prior FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA name Llewrodonte, it will be necessary to adopt d’Orbigny’s name of Nuculina for the genus. Superfamily ARCACEA. Famiry PARALLELODONTID-. Genus Cuculleea Lamarck. Cucullea Vam., Syst. des. An., 1801, p. 116; Bosc, Hist. Nat. Coq., ili., p. 121, 1802. Type C. (Arca) concamerata Martini. Tdonearca Conrad, Proc. Acad. Nat. Sci., 2d Ser., vi., p. 289, 1862. Type 7 “ppana Conrad, Cretaceous. Latiarca Conrad, of. cit., p. 289, 1862. Type Cucullea gigantea Conr., Eocene. The only general difference between the recent type of Lamarck’s genus and the fossils named by Conrad, is that the fossil shells are thicker. For some unknown reason Conrad regarded Latiarca as a subgenus of T7rigo- narca Conrad, which appears to be a valid and recognizable group, though perhaps rather close to Zrimacria. The genus Cucullea has not been reported from our Post-Eocene hori- zons. Professor W. B. Clark* has discussed the type species with numerous illustrations. I am inclined to believe that the Eocene of Virginia and Mary- land affords two species of Crcullea, C. gigantea Contr. (+ onochela Rogers) and C. ¢ransversa Rogers. The latter appears in the Chickasawan (Suessonian) Eocene at Gregg’s Landing, Alabama, and may be what Harris (Bull. Pal. No. 4) has called C. Saffordi Gabb, which he reports from the Midway. Whether this is correct or not, the Gregg’s Landing shells agree exactly with Maryland specimens of the same size. C. gigantea, abundant in Maryland, is not re- corded authentically from the Gulf States. The differences between these two forms is not confined to aged and young, but is equally marked between adults, though C. gigantea, especially, is quite variable. C. macrodonta Whit- field appears to be unknown in the northern Eocene, but is abundant in the Lower Eocene of the Gulf States. Its most conspicuous characteristic is the discrepancy between the sculpture of its two valves, which is often very marked. The Cucullea levis Tuomey, from the Eocene of Wilmington, North Carolina, has not been figured or sufficiently described, and must be regarded as a doubtful species. I have retained Cucullea in a distinct family from Arca, not because I * Bull. U. S. Geol. Survey, No. 141, p. 84, 1896. TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA 604. think there are probably family differences between the most nearly related recent species of the respective groups, but because some of the best paleon- tologists regard Arca and Cuculle@a as having reached their present status through very different lines of descent. Doubtless they converge in geologi- cal time, but the Avcéd@ appear to be a relatively very modern group, taken as a whole. The name Macrodontide used for this family on pages 516-17 must be dropped, since the generic name Jacrodon is preoccupied, and Parallelodon Meek proposed for the species which the former included; consequently, the family name must also be changed. Further study has also led me to the conclusion that the genus Cwcullarza Conrad, which is referred to Macrodon- tid@ on page 517, should rather be included with the true Arks, in spite of the fact that the hinge-teeth are arranged with much similarity to those of the Paleozoic group. This similarity is probably only superficial and due to other causes than inheritance from such forms as Parallelodon. FAMILY LIMOPSID/s. Genus TRINACRIA C. Mayer. Trigonocelix Conrad, Am. Journ. Conch., i., p. 12, 1865 (Z. cwzneus Conr.). Trinacria C. Mayer, Moll. Tert. du Mus. de Zurich, iii., p. 62, 1868. Trigonocelia Desh., Descr. An. s. Vert. bassin de Paris, i., p. 838, 1860. Not Zrigonocelia Nyst and Galiotti, Bull. Acad. Brux., ii., pp. 287, 347, 1835. This curious little genus is represented in the Claibornian by 7: ceneus Conrad (++ carinifera Lea), T. pectuncularis Lea, and T. ledoidea Meyer, which, described from a single worn valve, seems rather close to pectuncularis. The name 7rigonocelix, used by Conrad in his catalogue of Eocene fossils, appears to have been a typographical error; if not it would antedate Z7zvacrza, though no diagnosis was given. Trinacria Meekii n. s. PLATE 32, FIGURE 17. Oligocene of the Chipola beds, Chipola River, Calhoun County, and of the Alum Bluff beds, Oak Grove, Santa Rosa County, Florida; Dall and Burns, Shell small, solid, moderately convex, sculptured only with fine concentric lines ; anterior end rounded, posterior somewhat shorter, more pointed ; beaks FREE INSTITUTE OF SCIENCE 6 O TERTIARY FAUNA OF FLORIDA 5 low, with (in the adult) an almost linear depressed amphidetic area, interrupted by an oblique impressed subtriangular ligament pit which, though external, interrupts also the line of teeth ; interior smooth, muscular impressions large, not bounded by an elevated line; pallial line slightly indented below the posterior adductor scar; there are about eight anterior and six posterior teeth, small and delicate; basal margin smooth and nearly straight. Lon. 5.5, alt. 3.2, diam. 2.2 mm. This pretty little species recalls 7. mzrta Mayer and 7: Baudoni of the Paris basin, but is clearly distinct from either of the American species. Genus LIMOPSIS Sassi. The genus Zzmopsis is represented in the American Eocene, but, perhaps owing to the fact that they were deposited in comparatively shallow water, the Miocene and Pliocene of the United States have so far yielded no species of this genus. Lzmopsis aviculoides Conv. (+ “ Pectunculus” obliquus Lea) is found in the Claibornian at Claiborne Bluff and Wahtubbee, Mississippi. The shell figured by Cossmann (Suppl. Greg. Mon., p. 16, pl. 1, figs. 20- 21) as Limopsis perplana Contr. is distinct from any of the known species of that genus in this formation, especially by its smooth inner margins, and may take the name of L. Cossmannt. Limopsis radiatus Meyer is described by that author from Jackson, Mis- sissippi. It is very close to and doubtless the descendant of the ZL. aviculoides, but has a different sculpture. The latter, according to Gregorio, was referred to L. nana Desh. by d’Orbigny, which is an erroneous identification, as pointed out by Cossmann. Bronn did not make it, as erroneously indicated by Greg- orio (Mon. Faun. Eoc. Ala., p. 193), nor did Conrad or Heilprin. The typo- graphical errors in Gregorio’s work are almost endless, and this appears to be one of them. In the researches necessitated by the present work I have been obliged to go over this group in the Claibornian, and find the errors so numerous in every author who has treated of them, in spite of some rectifications by Cossmann, that I feel the student will find the results useful, and so include them here. The following groups of species have been referred erroneously to Limopsis. Trigonoarca Conrad, 1867. Type Cucullea maconensis Conr. This genus, which begins with large species in the Upper Cretaceous, is TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA 606 represented in the Eocene by several small, degenerate forms which have no descendants. They are: T. ellipsis Lea (Contr. Geol., fig. 56). A good species, not identical with Pectun- culus perplanus Conr. T. perplana Conrad (Limopsis perplanatus d’Orb.). Very like dechivis, but more rhomboidal and more flat. It is much larger than 7. edlipsis. T. corbuloides Conrad. This species has never been sufficiently described and is unfigured. By some blunder a specimen of 7. dechivis has been mounted as the type of corbuloides in the collection of the’ Academy of Natural Sciences. The descriptions, however, show that this specimen cannot be the original type. If it were, the name dechvis should be adopted. T. decisa (Conrad?). The original decisa is represented in the Academy’s collection by a specimen of Trinacria pectuncularis Lea, but this does not agree well with Conrad’s figure and brief description. Mr. T. H. Aldrich has obtained some specimens of a Claiborne 77zgonoarca which agrees much better with Conrad’s figure, and is probably the species he had in mind. It appears to be distinct from the others. T. dechvis Conrad. This is the largest Claiborne species and agrees well with Conrad’s figure (Journ. Acad. Nat. Sci., 2d Ser., iv., pl. 47, fig. 13) and original description. It appears to be rare. It is not a Zyivacria nor is it the same as Pectunculus minor, as asserted by Conrad and others. It has been collected at Wahtubbee as well as at Claiborne. The following species belong to Glycymerts (= Pectunculus) proper : G. tragonella Conrad (+ P. deltordeus Lea). This is very common at Claiborne and varies from trigonal to rounded, and from smooth to radiately ribbed. As the specimens intergrade completely, the mutations can hardly be named varieties. Conrad’s name was first printed (Am. Journ. Sci., xxiii., p- 342, Jan., 1833), though he did not figure the species. G. minor Lea (fig. 54). This species appears to me distinct from G. #igonella, to which it is most nearly allied. It differs in shape, is a thinner, wider, and more compressed shell. It reaches a length of nine millimetres, and the inner basal margins are sharply crenulated. Conrad’s reference of it to 7. declivis, as a synonym, is obviously erroneous. FREE INSTITUTE OF SCIENCE 607 TERTIARY FAUNA OF FLORIDA The Limopsis pectuncularis (Lea) Conr. is a Trinacria, but Cossmann seems to have found a single small valve resembling it which he identifies as an Arca, in which case it must belong to a distinct species. ,Gabb described (1873) a Limopsis ovalis from the Tertiary of St. Domingo which is probably Oligocene. It may be the same as L. subangularis Guppy, from the Ditrupa bed at Pontapier, Trinidad (Proc. U. S. Nat. Mus., No. 1110, 1896), but Gabb’s species is very briefly described and has not been figured. Guppy’s shell is also found in the Oligocene marl of Bowden, Jamaica. Famiry ARCIDZ:. Subfamily PECTUNCULINZ. Genus GLYCYMERIS Da Costa. Glycymeris Da Costa, Brit. Conch., p. 170, 1778 ; Humphrey, Mus. Calonnianum, p. 50, 1797. Type Arca glycymerts L. Tuceta Bolten, Mus. Boltenianum, p. 172, 1798 ; zb¢d., ed. 11., p. 120, 1819. First species Arca pilosa L. Axinea + Axineoderma, Poli, Test. utr. Sicil., 1., p. 32, 1791, and il., p. 254, 1795. Pectunculus Lamarck, Prodr., p. 87, 1799; Hist. An. s. Vert., vi., I, p. 47, 1819 (not of Da Costa ef al.). Type Arca pectunculus L. ? Deshagesia Berge, Conch.-buch, p. 80, pl. x., fig. 9, 1847. (@ err. typogr. for Des- hayesia.) Not Glycymerts Lam. et auct. aliis var. The history of this name has been detailed under NWacu/a and need not be repeated here. The Eocene species of the United States comprise, besides G. mznor and G. trigonella Conr., the larger G. staminea Conr. (+ G. Broderipii Lea), G. idonea Conr., all Claibornian, and G. fi/osa Conr., from the Jacksonian. The latter appears to include as synonymes “ Glossws” filosus Conr. (in Wailes’s Rep., 1854), daznze@a filosa Conr. (Pr. Ac. Nat. Sci., ix., p. 166, 1858), daznea mequistria and duplistyia Conr. (Am. J. Conch, i., p. 139, 1865). The two latter names were given to mutations which intergrade completely according to the large series I have studied. In the Vicksburgian Oligocene G. arctata Conr. (1848, of which Axinca mitercostata Gabb is a synonym, as well as the unfigured A. dc//asculpta Contr.), a very variable species, is found. It has been with little warrant united by Gabb with the Cretaceous G. hamula Morton of the Prairie Bluff horizon. TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA 608 The small Vicksburgian G. mississippiensis Conr. recalls the rounded form of the Eocene G. trigonella. In the Upper Oligocene of Bowden, Jamaica, is found the well marked G. acuticostata Sby., described from St. Domingo, and G. jamaicensis Dall. From the same horizon in St. Domingo Gabb has described G. approximans. The Eocene Pectunculus circulus Conr. (Mort. App., p. 7) has never been described or figured. An anonymous species from the Midway formation is mentioned by Harris in his monograph of that horizon. In the Upper Tertiaries of the Pacific coast are a number of ill-defined species. Pectunculus patulus Conr. was described (1849, Geol. Wilkes Expl. Exp.) from an internal cast; P. tens Conrad, which follows it, is equally unrecognizable; G. Kashevarovi Grewingk (Beitr., p. 352, 1850) is a well marked, strongly ribbed, probably Miocene species from Alaska; P. darbarensis Conr. (P. R. R. Rep., vi., p. 314, 1856) is hardly recognizable, and is referred to P. patulus by Gabb. There are several Chico-Tejon species. The recent dinea intermedia of Carpenter has been reported from the Californian Pliocene. Glycymeris jamaicensis n. s. Oligocene of the Bowden marl, Jamaica. This species has been referred to G. pennacea Lam. by Guppy and Gabb, but appears to be distinct. The specimens I have examined are all of moderate size, nearly circular, quite convex, externally sculptured with fine, even, radiating stria, impressed at intervals so as to give the effect of obsolete ribs, which are more apparent on the middle of the shell; on the beaks some of the threads are stronger; umbones low and plump; cardinal area impressed, narrow, short, and smooth ; teeth small, uninterrupted, about twenty-four in all, the line gently arcuate; inner margin fluted, with a slight insinuation near the base in front. Lon. 35, alt. 33, diam. 22 mm. Glycymeris pennacea Lamarck. Pectunculus pennaceus Lam., An. s. Vert., vi., 1, p. 51, 1819 ; Reeve, Conch. Icon. Pectiun- culus, pl. v., fig. 24, 1843. Pectunculus carolinianus Conr., Med. Tert. No. 1., cover p. 3, 1839. Pectunculus carolinensis Conr., Med. Tert., p. 63, pl. 35, fig. 2, 184g; Am. Journ. Sci., xli., p. 346, 1841. Pectunculus lineatus Heilprin, Trans. Wagner Inst., i., p. 103, 1887 ; not of Lamarck or Reeve. Not P. carolinensis Holmes, P.-P). Fos. S. Car., p. 15, pl. iii., fig. 4, 1860. FREE INSTITUTE OF SCIENCE 609 TERTIARY FAUNA OF FLORIDA Miocene of North Carolina, at Wilmington, Conrad; Pliocene of Domi- nica, West Indies, Guppy; Pliocene of the Caloosahatchie marl, Heilprin ; recent in the West Indies. This species is easily recognized by its nearly smooth surface and angulated outline. It appears to be rare. Glycymeris parilis Conrad. 3 Pectunculus parilis Conr., Proc. Acad. Nat. Sci., i., p. 306, 184f ; Med. Tert., p. 64, pl. 36, fig. 2, 184g, Older Miocene of Maryland at St. Mary’s River and Plum Point, Tilgh- man’s Station, Skipton, and Blake’s Cliffs; Burns and Harris. This characteristic species is rarely found in thoroughly good preser- vation. Glycymeris levis Tuomey and Holmes. Pectunculus levis T. and H., Pleioc. Fos. S. Car., p. 50, pl. 17, fig. 5, 1857. Pectunculus virginie Wagner (name only) on unpublished pl. 3, fig. 5, “de Bronn, Ind. Pal., i., p. 940, 1848 ; il., p. 283, 1849. Miocene of Waccamaw, South Carolina, Tuomey, and of Virginia (Wagner). This species differs by its smaller size and more wedge-shaped form from G. parilis, and from the young of G. paris of the same size by its subtrian- gular rather than circular outline, absence of any small ribs, and especially by its broader cardinal area and steeply arched line of larger hinge-teeth. Wagner’s name, though earlier, was never accompanied by any description. The plates are still in the possession of the Wagner Institute, and have no names engraved upon them, so the name given by Tuomey and Holmes takes precedence. (See Trans. Wagn. Inst., v., p. 11, pl. 3, fig. 5, 1897.) Glycymeris americana Defrance. Pectunculus americanus Defr., Dict. Sci. Nat., vol. 39, p. 225, 1829. : P. pulvinatus Conr., Fos. Vert. Form., p. 17, pl. 2, fig. 2, 1832; not of Lamarck. P. lentiformiés Conr., Fos. Tert. Form., 2d edition, p. 36, note, 1837; Med. Tert., No. 3, p. 64, pl. 36, fig. 2, 1845 ; Tuomey and Holmes, Pleioc. Fos. S. Car., p. 48, pl. 17, fig. 2, 1857 (senile stage). P. tricenarius Conr., Med. Tert., p. 63, pl. 35, fig. 1, 1845 (~ immature shell). P. carolinensis Holmes, P.-Pl. Fos. S. Car., p. 15, pl. 3, fig. 4, 1860. P. passus Conr., Med. Tert., p. 64, pl. 35, fig. 3, 1845. P. transversus Tuomey and Holmes, Pleioc. Fos. S. Car., p. 51, pl. 17, fig. 6¢, 1857 ; not of Deshayes, 1835, or Dubois ; (internal cast of young fassus.) P. tumulus Conr., Med. Tert., p. 72, pl. 41, fig. 4, 1845. TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA 610 P. quinguerugatus Conr., Am. Journ. Sci., xli., p. 346, 1841 ; Med. Tert., p. 63, pl. 34, fig. 3, 1845 ; Tuomey and Holmes, Pleioc. Fos. S. Car., p. 49, pl. 17, fig. 4, 1857. P. undatus Dall, Bull. Mus. Comp. Zool., xii., No. 6, 238, 1886, ex parte. Miocene of Jericho, New Jersey ; of Calvert and Charles Counties, Mary- land; Prince George and Dinwiddie Counties, the banks of the Nansemond River near Suffolk, and on the York River, and Petersburg, Virginia; Wil- mington and Cape Fear, North Carolina; Pliocene of the Waccamaw beds, South Carolina, and of the marls of the Caloosahatchie, Florida; living on the southeastern coast of the United States, in fifteen to sixty-five fathoms, from Cape Hatteras to the West Indies. When I wrote my report on the Blake Pelecypoda, I had not had an opportunity of studying well preserved G. fennacca, and was in doubt as to its relations. I also accepted the traditional identifications of the names given by Linnzeus, Lamarck, and other early writers to our American species. It would seem that several of these names can never be absolutely determined, and in the present synonymy I have dropped them and adopted the earliest name which unmistakably refers to our shells. The unusually long synonymy which the present species possesses arises from two causes,—carelessness and ignorance of the changes due to age. The large Glycymerts has two sorts of modifications,—one which is due to variation, and the other correlated with growth and senility. In the very young shell the surface sculpture is always sparser, more un- even, and sharper; in the adolescent specimen the ribs are usually well marked and extend clear to the base; the teeth are delicate and not inter- - rupted by an invasion of the cardinal area. In the adult this invasion begins, but otherwise the hinge is normal, the ribbing begins to become obscure dis- tally, and the cardinal area enlarges. In the senile shell the cardinal area is very large, only the ends of the arch of teeth remain, and these teeth are usually enlarged; the concentric sculpture, due to intermittent instead of steady marginal growth, becomes conspicuous. Individuals vary in regard to strength of sculpture and its lateral exten- sion; the two ends of the shell are rarely as clearly ribbed as the middle, and sometimes have no ribs. The size of the hinge-teeth varies considerably be- tween different specimens of the same size of shell; in general a larger car- dinal area and greater expansion of the valves near the hinge-line is correlated with larger teeth. Specimens differ in amount of inflation and in outline from nearly circular to transversely oval, and even sometimes a little oblique. FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA 611 When these two sets of mutations are surperimposed it naturally happens that the extreme instances are quite unlike; without connecting links one would, as Conrad and others have done, suppose them to represent distinct species. A very careful and conscientious scrutiny of a large number of specimens has resulted in the above synonymy. G. passa is the normal adult; G. lentifornus, the senile adult; G. #icenaria is a half-grown, well developed form; G. carolinensis Holmes is a variety with feeble ribbing, obsolescent at the ends of the shell; G. wansversa T. and H. (non Deshayes) is founded on the internal cast of a rather wide young shell; G. ¢mulus Conr. is founded on a rather inflated half-grown specimen. The only form which may possi- bly be varietal, but which I am inclined to refer to some pathologic cause, is G. quinquerugata. This is almost entirely confined to Duplin County, North Carolina. Well-marked specimens have on each dorsal slope, from the beaks laterally, three to six little irregular ripples, which are much more conspicu- ous in the young. These might indicate the presence of some parasite in the individual. They are never uniform or regular; some specimens have them only on one side, in others they are obsolete, and, finally, others do not have them; and between the normal americana and the gwinquerugata without ruge there is absolutely no distinction to be made. The recent shell is iden- tical with Miocene specimens and reaches fully as large a size. The preceding species have more or less distinct radial striation, whether there are ribs or not; in those that follow there is no radial striation but more or less distinct, fine, concentric sculpture and strong radial ribbing. Glycymeris subovata Say. Pectunculus subovatus Say, Journ. Acad. Nat. Sci., 1st Ser., iv., p. 140, pl. 10, fig. 4, 1824 ; Conrad, Fos. Tert. Form., p. 17, pl. 2, fig. 3, 1832; Med. Tert., p. 62, pl. 34, fig. 1, 1845 ; Emmons, Geol. Rep. N. Car., p. 286, fig. 207, 1858. G. subovata var. Tuomeyi Dall. LPectunculus subovatus Tuomey and Holmes, Pleioc. Fos. S. Car., p. 47, pl. 17, fig. 1, 1857. G. subovata var. plagia Dall. Oligocene: Vicksburgian of Martin Station, Florida ; Chipolan of Chipola River and Alum Bluff, Calhoun County, and Oak Grove, Santa Rosa County, Florida; Miocene of Walton County, Florida; of Dargan Point and Darlington, South Carolina; of Duplin County, Edgecombe County, Green County, and Wilmington, North Carolina; of Grove Wharf, James River, 4 TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA 612 Bellefield, Yorktown, and other points on the York River and on the Eastern Shore of Virginia, and Davis’s Mill, Choptank River, Maryland. Variety plagia Dall, Edgecombe County, North Carolina. Variety Zzomeyi Dall, Petersburg, City Point on James River, and near Suffolk, Nansemond River, Virginia. Shell asymmetrically developed, inequilateral, the impressed lines more or less arcuate and obsolete on the produced anterior side. This species is the oldest of those which reach the Upper Miocene. The Chipola specimens are slightly smaller than the average Miocene shell, but this may be an accident of collecting; otherwise they agree very well with Miocene specimens. The normal adult is subcircular, with radiating impressed lines, the inter- spaces being gently rounded and rather wide. The grooves are closer at the ends of the shell and the interspaces less rounded. In the young the shell seems to have close-set rounded ribs; in senile specimens the radial grooves are obsolete towards the base. The principal mutations of the normal adult are greater or less prominence of the rounded interspaces, greater persistence distally of the grooves, and smaller or larger, sparser or more crowded, hinge- teeth and areal grooving. In the variety Zomey: the alternate interspaces are not rounded but flat, forming channelled spaces, subequal to and between the ribs, which are often more or less flattened on top and obsolete distally. In the variety p/agza the shell is obliquely produced with the grooves obsolete laterally. The Oak Grove series contains many specimens in which intercalary incised lines appear on the rounded interspaces distally and the lines are much crowded at the ends of the shell. An occasional specimen turns up where the whole shell is nearly smooth, the incised lines being obsolete. In this state it is much like G. /evis T. and H. externally, but larger and more rounded dorsally. Glycymeris pectinata Gmelin. Arca pectinata Gmel., Syst. Nat., vi., p. 3313, 1792. Pectunculus aratus Conr., Am. Journ. Sci., xli., p. 346, 1841; Med. Tert., p. 62, pl. 34, fig. 2, 1845 ; Tuomey and Holmes, Pleioc. Fos. S. Car., p. 50, pl. 17, fig. 6, 1857. Pectunculus pectintformis Orb., Moll. Cuba, ii., p. 313, 1853; not of Lamarck. Pectunculus charlestonensis Holmes, P.-Pl. Fos. S. Car., p. 16, pl. 3, fig. 5, 1860. Pectunculus pectinatus Dall, Bull. Mus. Comp. Zool., xii., No. 6, p. 239, 1886. FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA 5 Miocene of Wilmington, Cape Fear, and Duplin County, North Caro- lina; Pliocene of the Waccamaw beds, South Carolina, and of the marls of the Caloosahatchie and Shell Creek, Florida. Recent, in two to one hundred and seventy-five fathoms, from the vicinity of Cape Hatteras, North Carolina, to the West Indies, Nicaragua, and Barbadoes. The differences upon which Conrad founded his species avatus are such as may be observed in any large series of the recent pectiatus. The ribs vary from twenty to forty in number, very greatly in prominency and adjacency, and the incremental lines from obscure to sublamellose. The truncation varies in amount and sharpness. In a variety carzzaza, the ribs, instead of being rounded, are more or less carinate, like those of acuticostata. Al\l the differ- ences of the fossils can be paralleled in the recent shells. Glycymeris duplinensis n. s. PLATE 34, FIGURES 6, 7. Miocene of the Natural Well and Magnolia, Duplin County, North Carolina; Burns. Shell small, rounded-triangular, solid, moderately convex, with pointed, small, low beaks and a flattened lunular area; sculpture of strong, distally bifurcated radial ribs, separated by slightly narrower channelled interspaces ; nine anterior and nine posterior ribs on the lateral slopes are smaller, while on the middle of the shell are about ten larger ribs; transverse sculpture of regularly spaced, elevated concentric lines overrunning the whole shell; cardinal area small and short, with three or four concentric angular grooves; teeth small, vertically striated, six or seven on each side, the line strongly arched and uninterrupted; anterior margin straight, base rounded, posterior slightly arcuate; basal inner margin with about ten flutings. Largest valve, lon. 9, alt. 10, diam. 6.5 mm. This pretty little species is readily distinguished from any of the varieties of G. pectinata by its bifurcated and prettily sculptured ribs. It seems to be rather abundant at the locality mentioned. ‘ Subfamily ARCINZ. Genus ARCA (Linné) Lamarck. Arca (L.) Lamarck, Prodrome, p. 87, 1799. Type 4. zoe Linné. In the selection of the ‘‘ Noah’s Ark Shell” as the type of the restricted genus, Lamarck followed the ancient usage and continuous practice of natur- TRANSACTIONS OF WAGNER 614 TERTIARY FAUNA OF FLORIDA alists. Bruguicre placed this species first in his list in 1789. Poli, who did not adopt the Linnean nomenclature but had two genera, one for the shell and one for the soft parts, called it Daphue and Daphneoderma in 1795. In 1835 Swainson gave it the name of Ayssoarca,; it was included in his section Les navicules by Blainville in 1825, though he did not name it Mavicula, as sometimes stated. Cyphosis Rafinesque, 1819, was probably intended to cover fossil species of this type, but as no described species were referred to it, it remains unrecognizable; Zhyas Gray (Figures of Moll. An., v., p. 24, pl. 358, fig. 4, 1857) is another synonyme, but the name was used for another group in 1835; Browne was not a binomial writer, and his Czéofa, used by Morch in 1852, also falls into synonymy. Lastly, Avcoptera Heilprin, based on the following species, does not present, when a large series is compared, any con- stant characters which would separate it from the restricted genus Arca. Before proceeding to describe the species collected it is necessary to review the nomenclature and settle on the characters of the subdivisions to be adopted. This has been a work of considerable labor; the inaccuracy of the diagnostic characters given in the text-books is so astonishing, when they are compared with a series of the species, that one is tempted to believe such diagnoses are written without any reference to specimens or, at best, with only a single specimen for comparison. The examination of over one hundred species of fossils and a majority of the known recent species of Avca has en- tirely confirmed the opinion expressed by several authors, that a gradual transition may be traced between the groups which have been described as genera and subgenera with extremely few exceptions. Subgenus BARBATIA (Gray) Adams. Barbatia Gray, Synops. Brit. Mus., 1840, p. (?); zb¢d., 1844, p. 81. Type Arca barbata L., H. and A. Adams, Gen. Rec. Moll., i1., p. 534, 1858. The type form of this group is tolerably regular and seldom deformed, like the typical Arks, from the anfractuosities of its station; the reticulated sculpture shows few irregularities ; the cardinal area is narrow with numerous grooves for the resilium, which form a series of elongated concentric lozenges on the area; the shell is not conspicuously truncate or keeled; the teeth are small and vertical in the middle of the series and towards the end diverge distally and become larger and more distant. In some species these distal teeth are often broken up, like those of Caucul/@a, but this feature is not con- stant in the species. Several groups or sections are recognizable, though FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA ») they merge into one another through their peripheral species. Such are the following : Group of A. darbata L. (Barbatia s.s.). This includes A. (B.) méssissippiensis Conrad from the Vicksburgian Oligocene. Group of A. candida Gmelin (Calloarca Gray, 1857, + Plagiarca Conrad, 1875).* This includes A. cuculloides Conrad (+ A. “ima Conrad, 1847, not of Reeve, 1844, = A. Conuradi Desh.) from the Jacksonian; A. mary- landica Conrad and A. avcula Heilprin, Upper Oligocene and Older Mio- cene; and several other species. Litharca (lithedomus) Gray, 1840, is probably based on a specimen of A. candida, which had grown in the burrow of a Lithodomus. Upper Cretaceous to recent. Group of A. propatula Conrad (Grancarca Conrad, 1862) = A. hians Tuomey and Holmes, 1855, not of Brown, 1842; nor of Reeve (? = A. protracta Rogers, 1837, not of Conrad, 1847). Miocene. Group of A. centenaria Say (Striarca Conrad, 1862). Miocene. Group of A. donaciformis Reeve (Acar Gray, 1847, + Daphnoderma Morch, 1853, + Mossularca Cossmann, 1887). Eocene to recent. In Striarca the lozenge occupied by the ligament and its transverse grooves for the resilium cover the entire cardinal area; in typical Acar the lozenge is obliquely directed backward, leaving the anterior part of the area bare ; in Hosswlarca the lozenge is small, very short, and directly between the beaks, leaving a bare space before and behind it. A. c@/ata Conrad (A. Adamsi Shuttleworth) is a typical Hosswlarca. Group of A. heterodonta Desh. (Les Cucullaires Desh., 1860; Cucullaria Conrad, 1869, + Wemodon Conrad, 1869). Cretaceous (Ripley) to recent. In the Barbatias as well as in Glycymeris (Pectunculus auct.) the growth of the shell often results in a greater or less absorption of the middle part of the series of teeth; the distal teeth are always more or less oblique, especially those behind the beaks. In Czczllaria the latter are almost, if not quite, * Plagiarca is based on Barbatia carolinensis Conrad, 1875 (Ripley beds of North Carolina), not Arca carolinensis Wagner, 1847, nor A. (WMoétia) carolinensis Conrad of 1862. Polynema Conrad (Kerr. Geol. Rep. N. Car., 1875, App. A., p. 4), based on Barbatia lintea Conrad, 1875 (not Arca Zintea Conrad, Dead Sea Expedition, 1852), does not appear to differ from Plagiarca or Calloarca in any characters of importance. The name Polynemza is, at any rate, preoccupied in Entomology since 1833.” Mavicula aspersa Conrad and Barbatia aspersa Conrad, 1855 (not of Philippi, 1836), are synonymes of A. cuculloides. TRANSACTIONS OF. WAGNER TERTIARY FAUNA OF FLORIDA 616 parallel with the hinge-line. Consequently, it may follow that in the process of growth the same individual may at an early stage have a series of vertical median denticles, and at a later stage may present a hiatus destitute of teeth between the anterior and posterior parts of the series. Judging from the species I have been able to examine, the entire narrow cardinal area is orig- inally covered by the ligament, but the grooves containing the resilium extend very obliquely backward from the beaks, as in typical Acar. Notwithstanding the resemblance of the hinge in these Tertiary and recent species to that of the Paleozoic and early Mesozoic Parallelodon, 1 am of the opinion that the relations of the former are really closer with the true Arks, and that the similarities will prove to be analogical rather than homologous. The recent abyssal species I have formerly referred to Macrodon should probably be grouped under Cucullaria. Verrill has recently proposed to separate generically the above-mentioned recent species from forms like A. heterodonta Desh., the type of Cucullaria, and to call them Bentharca. The degree of inclination of the anterior teeth in these shells is hardly more than a specific character in my opinion, differing but slightly between many of the species, though the extremes of the series, taken alone, differ widely. Group of A. rubrofusca Smith (Lessarca Smith, 1876). Umbones nearly terminal, equivalve, hinge-line arched with an edentulous hiatus in the middle, sculpture concentric, area lineal, with a central very small ligament. This occupies to Barbatia much such a relation as Lathyarca does to Scapharca. Group of A. tortuosa L. (Trisidos Bolten, 1798, -+ Trzsis Oken, 1815). A small group of thin shells with a long, straight hinge-line and many small similar teeth, the valves more or less spirally twisted. The latter character is not particularly valuable in classification, but the group is easily recognized. Group of A. celox Benson (Scaphula Benson, 1835, not of Swainson, 1840; Scaphura Gray, 1847, by typographical error). Small, keeled, smooth externally, inhabiting Indian River. The soft parts do not appear to have been studied. Subgenus NOETIA Gray. Noétia Gray, Syn. Cont. Brit. Mus., 1840; Agassiz Nomenclator, Mollusca, 1842. Type Arca reversa Gray. FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA Shell equivalve, inequilateral; the beaks anterior, opisthogyrate, rather adjacent ; ligament transversely grooved, lozenge shaped, not occupying the whole cardinal area; posterior slope of the valves usually longer, subtruncate, or bounded on either side by an umbonal keel or ray; tooth-line rather long, terminal teeth often A-shaped. This group is American and Indo-Pacific in its recent distribution; the known fossils are all American. Besides those enumerated in this paper, Guppy has described from Trinidad Arca trinitaria (Manzanilla) and A. cen- trota (Matura), both of which belong to this group. The former might pass for an ancestor of the (now Pacific) A. reversa, while A. centrota, probably a Miocene species, offers a diminutive facsimile of A. “mula. Arca trapesia Desh., from West Mexico, and A. Martini Recluz, 1852, from Santa Caterina, Brazil, belong to this group. The latter is probably the shell living in the Gulf of Paria, which Guppy has referred to his A. centyota. They are very similar, and the living shell may perhaps be the unfigured A. dusulcata of Lamarck. The name Arca Martini is preoccupied by Bolten, and must be dropped. A. hemicardium Koch, as figured by Philippi, also belongs here. This subgenus is intermediate between the typical Arks and Scapharca. The original type has the anterior side of the shell longer and the posterior side short and truncate, but in JV. ponderosa the two sides of the hinge are subequal, and in the fossils the posterior side is much longer than the ante- rior. The definition in the text-books, drawn from A. reversa, must therefore be materially modified to be true of the very natural group to which it belongs. Subgenus SCAPHARCA (Gray) Dall. Scapharca Gray, P. Z. S., 1847, p. 206; H. and A. Adams, Gen. Rec. Moll., i1., p. 537, 1858. Type, 4. imeguivaluis Brug. It is a matter of some difficulty to decide which of the various names bestowed at various times by Gray should be regarded as most inclusive and predominate in the necessary consolidation of the group. The names Sezz/za, Argina, Lunarca (and, according to Agassiz, Voétia, though Gray does not mention it in his list of 1847) appeared first without diagnosis or figures in the little manual entitled “ Synopsis of the Contents of the British Museum,” prepared for the use of visitors to that institution. According to the rules of nomenclature, these names were not fully established either by their nude in- sertion in this list or in that of the synonymy of 1847. The latter contained, in addition, Avadara Gray for A. antiquata and Scapharca for A. ineguivalvis, TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA 618 neither of which were defined. So far as I have been able to discover, the proper definition of all these names was first made in Adams’s Genera in 1858, so that as regards priority all stand on a practically equal footing. Anadara was not adopted by the Adams brothers, who placed it in the synonymy of an unacceptable polynomial of Klein, and of all the names Scapharca, as used by Adams, comprises by far the larger number of species. I have therefore decided to adopt it in a subgeneric sense, reducing the less tenable names to sectional rank, As thus understood, Scapharca comprises the following groups or sections: Group of A. senilis Lam. (Senilia (Gray, 1840) Adams, 1858.) Heavy, trigonal, equivalve, with a short furrowed area; beaks proso- gyrate; with a smooth epidermis; with the hinge-teeth separated by a sinus into two straight subequal short series; both valves similarly sculptured ; inhabiting brackish water. Group of A. pexata Say. (Argina (Gray, 1840) Adams, 1858.) Thin, ovate-oblong, rounded; beaks prosoccelous, with the right valve smaller, the cardinal area opisthodetic, or nearly so, and very narrow, the hinge-teeth in two series—the anterior shorter, usually irregular or broken up, the posterior longer, normal; the epidermis imbricated and profuse; inhabiting salt water. Group of A. ineguivalvis Brug. (Scapharca (Gray, 1847) Adams, 1858.) Moderately thin, elongate-ovate, with prosoccelous beaks, rather narrow cardinal area, not wholly covered by the ligament and usually with concentric resiliary lozenge-like grooving; tooth series uninterrupted, the teeth small, similar, somewhat larger and more oblique distally; the right valve smaller, the sculpture on the two valves usually similar or not markedly discrepant ; the epidermis much as in Argina. Group of A. zxcongrua Say. (Cunearca Dall.) Thin, trigonal, inflated, with erect beaks; the cardinal area short, amphi- detic, equilateral, set off by deep grooves from the rest of the sculpture, smooth or transversely striated, without furrows ; hinge-teeth divisible into two series, smaller proximally, larger and more oblique distally, often more or less A-shaped; the right valve smaller; sculpture of the two valves obviously discrepant; the epidermis smooth or not pilose. FREE INSTITUTE OF SCIENCE 619 TERTIARY FAUNA OF FLORIDA Group of A. antiquata L. (Anadara (Gray, 1847) Adams, 1858, in synonymy, + Anomalocardia Adams, 1858, not of Schumacher, 1817.) Shell heavy, trigonal or oblong, inflated, with prosoccelous beaks, with a wide area wholly covered by the ligament and usually with numerous furrows for the resilium forming concentric lozenges ; teeth similar, in a long, uninterrupted series, slightly larger and more oblique distally; valves equal and similarly sculptured; epidermis usually pilose and profuse. The young shell is often and the adult sometimes auriculate behind. The transition to Scapharca s. s. is very gradual and complete. Group of A. pectunculoides Scacchi. (Lathyarca Kobelt, 1891.) Shell small, usually abyssal, inflated, with prosogyrate beaks and a rather narrow but long furrowed area, the hinge-margin nearly or quite as long as the shell; teeth few, oblique, in two series, often separated by a wide gap in the centre; the right valve smaller, the sculpture of the two valves often very discrepant; epidermis usually imbricated. These small deep-water Arks go back to the Eocene in time and form a very recognizable group, related to Scapharca as Lissarca is to Barbatia. Subgenus LUNARCA (Gray) Adams. Lunarca (Gray, 1840) H. and A. Adams, Gen. Rec. Moll., ii., p. 541, 1858. The only species known, L. costata Gray, is not unlike Argiva, but has no anterior taxodont teeth. These are replaced by a single, large, horizontal tooth in the right valve, fitting into a socket in the left valve, forming a remarkable exception to the usual rule in this family. In a manuscript of Stimpson’s in my custody he queries whether this shell is not a monstrous malformation of a specimen of Arvgzza. I have never seen a specimen and have never been able to purchase one from any dealer, so I am unable to express a valuable opinion on this point, but perhaps the question is worth investigation. In the descriptions of the species which follow, for convenience of recog- nition the subgeneric name followed by the sectional name in parentheses will introduce the paragraphs relating to each form. Arca Wagneriana Dall. PLATE 39, FIGURES 6, 7. Arca (Arcoptera) aviculeformis Heilprin, Trans. Wagner Free Inst. Sci., i., p..98, pl. 13, figs. 32, 32a, 1886. TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA Not Arca aviculeformts Nyst, Tabl. Synopt., p. 12, 1848; = Arca aviculoides Reeve, 1844, not of De Koninck, 1844. Arcoptera aviculeformis Harris, in Dana, Man. Geol., 4th ed., p. goo, fig. 1510, 1895. Pliocene marls of the Caloosahatchie, Shell Creek, and Myakka River; Heilprin, Willcox, and Dall. This fine species is quite variable in the development of the extended wings which suggested Professor Heilprin’s name. In many specimens the posterior wing does not exceed that usual in A. occtdentalis, while in others it may extend an inch beyond the rest of the shell. The anterior wing is less prominent and a little more constant, but is frequently paralleled by fossil and even by recent specimens of A. occidentalis Phil. So far as yet known, this species is confined to the Floridian Pliocene. The character of the cardinal area is similar to that of A. zoe. Arca occidentalis Philippi. Arca occidentalis Phil., Abbild. u. Beschr., ii1., p. 14, pl. xvi. 0, fig. 4 a—-c, 1847. Arca zebra Swainson, Zool. Ill., No. 26, pl. 118, 1831 ; ex parte. Arca noe of many authors, not of Linné. Oligocene of the Bowden beds, Jamaica, Guppy, Henderson, and Simp- son; Miocene (?) of Curagao, U.S. Fish Commission ; Pliocene of the Caloosa- hatchie marls, Florida, Dall; Pleistocene of the Florida Keys, Yucatan, and most of the West Indian Islands; recent in the Antilles generally, and along the eastern coast of the United States northward to the vicinity of Cape Hatteras, North Carolina. A careful comparison shows that the American shell should not be united with the Mediterranean A. zo@. The restricted A. zebra, according to Swain- son, comes from the Mediterranean, but Reeve refers it to Manila. The west American recent analogue appears distinct. Although in taking up the species I doubted if the Bowden fossil could be the same as the recent shell, I am obliged after careful comparisons to regard them as identical. The species is very rare in the Caloosahatchie marls, and only represented in my collection from them by a few young valves. Arca umbonata Lamarck. PLATE 38, FIGURES 4, 4a. Arca umbonata Lam., An. s. Vert., vi., p. 37, 1819; zbzd., 2d ed., vi., p. 432, 1835 (syn. partim excl.) ; Philippi, Abbild. u. Beschr., ii., p. 13, pl. xvii. 4, fig. 3 a—c, 1847. Arca noe Stimpson, S. 1. Checklist, E. Am. Mar. Shells, p. 2, 1860. FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA Arca imbricata (Brug.) Dall, Bull. U. S. Nat. Mus., No. 37, p. 40, 1889; Heilprin, Trans. Waener Inst., i., p. 118, 1887. Arca Listert (Tryon) Heilprin, Trans. Wagner Inst., 1., p. 118, 1887. Barbatia Bonaczyt Gabb, Geol. San Domingo, p. 254, 1873. Oligocene of the Chipola beds, Calhoun County, Florida; of the Ballast Point silex beds, Tampa Bay, Florida; of the Alum Bluff sands at Oak Grove, Santa Rosa County, Florida. Also in the Pleistocene of the Florida Keys and the Antilles, and living from Cape Hatteras, North Carolina, south to Santa Caterina, Brazil, and throughout the Antilles. Like all the group, this nestling species is variable in form according to its station, but I have been unable to find any characters to separate the fossil and recent shells when allowance is made for the deformations alluded to. It may be distinguished from A. aguila Heilprin by the less alate anterior end and smoother ribs, otherwise they are closely allied. The name zmdvicata, cited as of Bruguiére, is somewhat doubtfully applicable to this shell, and no diagnosis was given in the Encyclopédie Methodique. It probably retreated to warmer waters during the Miocene invasion of Florida and did not succeed in returning until the end of the Pliocene, as it has not turned up in the Caloosahatchie marls. The form doubtfully identified by Professor Heilprin with A. Lesteri is connected by a fuller series with the others. Area aquila Heilprin. PLATE 31, FIGURE 12. Arca aquila Heilprin, Trans. Wagner Inst., i., p. 97, pl. 12, fig. 31, 1887. Pliocene marls of the Caloosahatchie River, Florida; Willcox and Dall. This very neat species appears to be somewhat rare, and has only been found at the original locality as yet. Area paratina n. s. PLATE 33, Ficure 14. ?= A. (Byssoarca) protracta Conr., Journ. Acad. Nat. Sci. Phila., 2d Ser., i., p. 126, pl. 13, fig. 36, 1848 (not of Rogers, 1837) = sudprotracta Heilprin, 1881. Oligocene of the Chipola beds on the Chipola River, and of the lower bed at Alum Bluff, Calhoun County, Florida; Dall and Burns. Shell elongated, not very thick or high, not much distorted, but with a variable byssal gape, inequilateral, the beaks at or near the anterior fourth; moderately alate in front and behind; beaks low, pointed, not inflated, their TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA 622 apices slightly prosogyrate, cardinal area long, narrow, lozenge-shaped, flattish, with longitudinal strize, the site of the resilium marked on each valve by two grooves forming a small triangle, within which are traces of the inception of other grooves; sculpture chiefly of fine radial riblets overrunning and some- what imbricated by not prominent lines of growth; the radials which end on the margin of the byssal foramen are perceptibly finer than the rest, those on the posterior dorsal slope are more or less fasciculated, the ends of the fascicles dentating the posterior margin; on the dorsal anterior part the riblets increase somewhat in size, but are not fasciculated; the dorsal border in front is anterior to the rest of the margin; between the dorsal posterior extreme and the ventral posterior angle there is often an irregular but not deep emargina- tion; the borders of the byssal foramen are irregularly emarginate; interior smooth, the margin denticulated by the sculpture except at the foramen; hinge-line straight, minutely denticulate; the teeth in the centre smaller, those towards the ends inclined outward slightly, above, and a little larger; there are about twenty-three anterior and forty posterior teeth, with no marked hiatus between the series. Lon. of shell 28, alt. of hinge-line 8.5, of beaks 10, diam. at the umbonal part 10 mm. It is quite possible that the shell grows to a considerably larger size. This species is distinguishable at once from the A. occidentalis of the same size by its uniformly more delicate and much more numerous ribs, and by its greater length in proportion to its height. It is also usually less alate behind, and of more uniform, undistorted shape. Differences of form and proportion seem to separate it sufficiently from A. swbprotracta Heilprin. Arca hatchetigbeensis Harris from the Lignitic or Chickasawan stage is shorter and more finely sculptured, though closely related. Arca bowdeniana n. s. PLATE 33, FIGURE 12. Oligocene of the Bowden beds, Jamaica, and Pliocene of Limon, Costa Rica; Bland, Henderson, and others. Shell small, inflated, somewhat irregular, very inequilateral, the beaks almost posterior; dorsal slope conspicuous; its outer border with a stout keel and its surface somewhat excavated; beaks small, pointed, prosogyrate; car- dinal area wide, lozenge-shaped, flattish, with a few grooves for the resilium forming a smaller lozenge near the beaks; sculpture as in A. wmbonata, the imbrications close and subnodulous; shell not alate in front and with the FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA anterior margin nearly vertical from the hinge-line; posterior end obliquely truncate, the basal angle most extended, the dorsal one forming nearly a right angle; anterior teeth ten, posterior twenty-seven, with no noticeable hiatus in the line, the teeth resembling those of A. pavatina but proportionally larger ; interior smooth, the posterior end with a few flutings, the rest of the margin entire; the byssal foramen narrow and its margins encroaching only moder- ately on the valves. Lon. 15, alt. of hinge-line 6, of beaks 8, diam. (greatest posteriorly) 9 mm. This odd little shell is peculiar in being narrower near the very anterior beaks and widest about the middle of the posterior slope. It appears to be easily discriminated from the other species of this variable group known to the region. Subgenus BARBATIA (Gray) Adams. Section Calloarca Gray. Barbatia (Calloarca) marylandica Conrad. Byssoarca marylandica Conrad, Fos. Medial Tert., p. 54, pl. 29, fig. 1, 1840. Barbatia marylandica Conr., Proc. Acad. Nat. Sci. Phila. for 1862, p. 580, 1863. Oligocene of the Ballast Point silex beds, Tampa Bay, the lower (Chipola) bed at Alum Bluff, the Chipola marl of the Chipola River, Florida ; older Miocene of Jericho, Cumberland County, New Jersey; Middle Miocene of Plum Point, Calvert Cliffs, and Centreville, Maryland; Willcox, Burns, Dall, and Harris. Possibly also in the Jacksonian. Careful comparisons of typical material show no specific differences between the Miocene and Oligocene shells. Barbatia (Calloarca) irregularis n. s. PLATE 33, FIGURE 5. Oligocene of the silex beds at Ballast Point, Tampa Bay (fragment) ? Pliocene marls of Shell Creek, Alligator Creek, and the Caloosahatchie ; Dall and Willcox. Shell thin, elongate, irregularly distorted; beaks prosogyrate; at the anterior third rather low and compressed; cardinal area long, rather narrow, with very numerous (twelve) concentric grooves ; surface irregular, sculptured with numerous fine radiating, somewhat imbricated ribs, of which those in front of the beaks and on the posterior dorsal slope tend to be larger and more elevated; there is a tendency to alternate or pair among the ribs in some specimens; the imbrications or nodules on the ribs are somewhat TRANSACTIONS OF WAGNER ODA ev TERTIARY FAUNA OF FLORIDA regularly spaced and correspond to elevated concentric lines in harmony with the lines of growth ; the posterior dorsal slope is bounded by rounded ridges radiating from the beaks; the posterior cardinal margin is elevated and angular with more or less of a depression between it and the radial ridge on each side; the byssal foramen is wide and irregular; the hinge-line is long and straight; the teeth, vertical and very small medially, are sometimes obso- lete in the middle of the hinge; distally they become rather distant and quite oblique, as well as larger; the internal margin, though irregular, is not fluted. Lon. of adult 51, alt. 25, diameter 20 mm. This species is distinguished from 4. marylandica by its smaller altitude, its coarser and more prominent sculpture, and more irregular hinge; the beaks are also more anterior. Barbatia (Calloarca) arcula Heilprin. PLATE 33, FIGURE 4. Arca arcula Heilprin, Trans. Wagner Inst., i., p. 118, pl. 16, fig. 65, 1887. Oligocene of the Ballast Point silex beds, Tampa Bay, Florida; Willcox. Shell subovate, thin, inflated, the beaks low and prosogyrous; the cardinal area narrow and very closely and minutely furrowed longitudinally, the fur- rows showing a slight angle behind the beaks ; sculpture of close set, fine radial ribs, rather regularly imbricated at successive lines of growth; on the poste- rior dorsal slope are six or eight nodulous larger ribs; the beaks are situated a little behind the anterior third; byssal foramen narrow, very anterior; hinge with a few large A-shaped teeth at the ends, the middle teeth vertical, small, or even obsolete mesially ; margins of the valve slightly or not at all crenu- lated by the sculpture. Length of shell 47, of hinge-line 30, height 31, diameter 26 mm. This species is very evenly and regularly fluted at the imbrications, dif fering in that respect from any of the other species mentioned here. It is notable also for its inflated and thin valves and the bluntly truncate posterior end, though the latter may be abnormal. Barbatia (Calloarca) cuculloides Conrad. Arca cuculloides Conr., Fos. Tert. Form., No. 3, p. 37 (not fig’d), 1833. Byssoarca lima Conr., Journ. Acad. Nat. Sci. Phila., 2d Ser., i., p. 125, pl. 13, fig. 23, 1848 ; not Barbatia lima Rve., P. Z. S., 1844. Cucullearca lima et cuculloides Conr., Am. Journ. Conch., i., p. 11, 1865. FREE INSTITUTE OF SCIENCE 625 TERTIARY FAUNA OF FLORIDA e Navicula aspersa Conr., Wailes, Agr. and Geol. Mississippi, p. 289, pl. 14, fig. 5 (young shell), 1855. Navicula aspera Conr., Proc. Acad. Nat. Sci. Phila., vii., p. 258, 1855 ; not Arca aspera Phil., Moll. Sicil., 1836. Upper Eocene (Jacksonian) near Claiborne, Alabama; Jackson, Missis- sippi; Cleve County, Arkansas; and in the Lower Oligocene at Vicksburg, Mississippi. This fine shell was separated from the true Arks by Conrad because in the fully adult specimens the distal teeth are usually (though not invariably) broken up into granular parts. This character occurs occasionally in individ- uals or particular species in most groups of the genus Avca and is too mutable to be taken as a basis for a genus. The other Vicksburg species, Barbatia mississippiensis Conr. (of. cit., 1848, p. 125, pl. 13, fig. 32), is distin- guished from A. cuculloides by its smaller size, finer sculpture, and the absence of any radial ridges setting off a posterior area as in the latter species. These ridges are very strong in the young, in which also the distal teeth are entire, giving the young shell such a different aspect that Conrad described it as a distinct species. Conrad described another Arca, belonging to the section Scapharca, under the specific name of mzssesseppiensis, in the same paper (p. 125, pl. 13, figs. 11, 15), which appears to be that figured by Lesueur in his Walnut Hills Fossils, pl. 5, fig. 8, 1829. This species may take the name of A. (Scapharca) Lesueurt, The Barbatia mississippiensis was also well figured by Lesueur on the same plate, figure 9. The Arca rhomboidella Lea, Contr. Geol., p. 74, pl. 2, fig. 52, from the Claibornian appears to be referable to Scapharca. We have it also from Lisbon, Alabama, the Eocene of Orangeburg, South Carolina, and according to Haldeman from the Eocene of Virginia, the exact locality not being recorded on the label. I suppose it must have been through an accidental confusion that Cossmann came to identify B. caculloides with this species. Omitting to notice that Conrad described his shell as two and a half inches long, Gregorio (0. cit., pl. xxiv., figs. 17-20) has figured a specimen of A. rhomboidella three millimetres long as A. cuculloides Conrad. It seems singular that he should not have noticed its practical identity with the figure of Lea which he reproduces on the same plate (fig. 28). Cossmann has very properly united the two, though he did not see that neither represented A. cuculloides of Conrad. Gregorio’s figure very fairly represents A. rhomboid- ella, which, however, reaches a length of over twenty millimetres in the adult TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA ° state. It is possible it may be a Barbatia, to which group I at first referred it, but after a complete study of all our fossil Tertiary species I concluded it would best be referred to Scapharca. Barbatia (Calloarca) phalacra n. s. PLATE 33, FIGURE 3. Oligocene of the Chipola marls, Chipola River, and of the Oak Grove sands, Florida; Burns. Shell thin, moderately convex, equivalve, inequilateral; the prosogyrate beaks within the anterior fourth low and somewhat compressed; sculpture of very numerous fine, even, mostly dichotomous riblets without nodules or reticulation over the whole shell, crossed only by feeble incremental lines; cardinal area very narrow with a few longitudinal grooves; hinge-teeth small, short, and vertical mesially without any gap in the series, distally longer, larger, and more oblique; hinge-line 44 of the whole length; internal margin of the valves.smooth, byssal gape inconspicuous. Lon. 23.5, alt. 11, diam. g mm. This is a very modest and neat little species which does not seem identi- fiable with any of the others. It is, perhaps, nearest to B. mussessipprensis Conrad, but is smaller, less flattened, and more regular. Barbatia (Calloarca) candida Gmelin. Arca candida Felbling?, Chemnitz, vii., p. 195, pl. 55, fig. 542. Arca candida Gmelin, Syst. Nat., vi., p. 3311, 1792. Arca Felblingz Bruguicre, Ency. Meth., p. 195, 1797. Arca jamaicensis Gmelin, Syst. Nat., vi., p. 3312, 1792. Oligocene of the Bowden beds, Jamaica, of the Chipola beds at Alum Bluff and on the Chipola River, Florida; Pliocene of Trinidad; Pleistocene of the Antilles generally, and recent from Cape Hatteras, North Carolina, to Brazil at Santa Caterina, and possibly the African coast. The fossils show no diagnostic features by which I can separate them from the recent shells. There are some difficulties in the nomenclature of this species which I have not the literature to straighten out. As far as Iam now able to ascer- tain, the first name applied to this shell was candeda, and the first binomial Latin name was that of Gmelin. It is a well-known West Indian species conspicuous for its large size, white shell, and compressed, flattish valves. It is quite possible that some of the early authors named this wide-spread species FREE INSTITUTE OF SCIENCE 627 TERTIARY FAUNA OF FLORIDA more than once, and in this connection the A. ovata and complanata should be examined. Another species which seems distinct is represented in the collection by a number of young valves from the Oligocene of Bowden. Section Granoarca Conrad. Barbatia (Granoarea) propatula Conrad. Arca propatula Conr., Proc. Acad. Nat. Sci. Phila., 1., p. 323, Dec., 1843; Fos. Med. Tert., p. 61, pl. 32, fig. 1, Jan., 1845. Arca hians Tuomey and Holmes, Pleioc. Fos. S. Car., p. 34, pl. 14, figs. 4, 5, 1855, not of Bronn, 1842, or Reeve, 1844. Granoarca propatula Conr., Proc. Acad. Nat. Sci. Phila. for 1862, p. 580, 1863. Miocene of Virginia, on the James River below City Point, Petersburg, and on the Ware River, Gloucester County, Conrad, Tuomey, and Ruffin; Darlington, South Carolina, Burns; Sumter District, South Carolina, Tuomey. The differences separating Conrad’s shell from Tuomey’s are merely individual mutations. The section was established by Conrad on account of the granular breaking up of the distal teeth, a feature of little systematic value. It may be retained, if at all, for Barbatias of elongate form, mesially compressed, with coarse even ribbing, not reticulated, and a very narrow byssal gape. Arca protracta Rogers (Trans. Am. Phil. Soc., v., p. 332, 1835, and vi., pl. 26, fig. 5, 1839) from the Miocene of Prince George County, Vir- ginia, probably belongs to the same section, but I have not seen a specimen. This must not be confounded with Arca protracta Contr. from the Vicksburgian described in 1848, which is a typical Avca and will take the name of Arca subprotracta Weilprin. Hon. T. H. Aldrich reports it from the Eocene. A. protracta Rogers is figured as having quite regular and rather small teeth, which may be partly due to the influence of age, the type having been evidently a very old specimen. It seems to be rare, and I have never been able to examine a specimen. Barbatia (Granoarea) virginize Wagner. PLATE 32, FIGURE 23. Arca virguue W. Wagner, Trans. Wagner Inst., v., pl. 1, fig. 3; Bronn, Index Pal. Nomencl., p. 99, 1848; Syst., p. 283, 1849. Miocene of Virginia; Wagner (Nansemond River ?). The founder of the Wagner Institute, Professor William Wagner, in the 5 TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA early thirties made some paleontological collections in Virginia and the adjacent parts of North Carolina. Some of the species appeared to be new and were named and figured by Professor Wagner, who had three fairly good lithographic plates prepared, of which a certain number were distributed. In Bronn’s Index Paleontologicus Wagner’s names are catalogued and the plate references given. A large number of copies of the prints and some of the original type specimens are still in existence and in the possession of the Wagner Institute. Among them are two Arcas, both of which appear to be good species, not otherwise named, and which will be included in this paper. Arca virginia is a large, solid, elongated shell, equivalve but very inequi- lateral, the beaks being situated near the anterior fifth of the length, low and prosogyrate, distant, and separated by a wide cardinal area with numerous (nine) slightly angular longitudinal concentric grooves; sculpture of about twenty-five strong radial ribs, smaller on the posterior dorsal area, somewhat flattened, and on the posterior part with a shallow, wide mesial furrow ; hinge- line 14 as long as the shell; teeth vertical, in two series, beginning mesially very small, distally larger, and with a tendency to break up or become irregu- lar; muscular impressions deep; margin fluted in harmony with the ends of the ribs. Lon. 83, alt. 52, diam. 42 mm. This shell is about midway in its characters between Larbatia (Grano- arca), Anadara, and Scapharca, illustrating very well the manner in which the subordinate groups of the genus Arca intergrade. It seems quite surprising that so large and conspicuous a shell should not have been collected and described by other paleontologists. Section Striarca Conrad. Barbatia (Striarca) centenaria Say. Arca centenaria Say, Journ. Acad. Nat. Sci. Phila., rst Ser., iv., p. 138, pl. 10, fig. 2, 1824. Striarca centenaria Say, Proc. Acad. Nat. Sci. Phila. for 1862, p. 580, 1863. Older Miocene of Jericho, Cumberland County, New Jersey, and in the Virginia Miocene at Coggin’s Point, Petersburg, Grove Wharf, on the James River, and the Miocene beds of the York River; Burns and others. This isa remarkably characteristic shell, and I believe has no synonymes. The erosion which acts upon fossils has in nearly all cases hollowed out the teeth, so that they look as if naturally grooved or hollow, and in the exam- ination of many specimens only one or two were found in which any large FREE INSTITUTE OF SCIENCE 629 TERTIARY FAUNA OF FLORIDA number of the teeth were intact. Conrad seems to have supposed that this condition of the teeth was normal, but I regard it as a phenomenon of erosion merely, and have noticed similar excavations in the teeth of other species. Section Acar Gray. Barbatia (Acar) reticulata Gmelin. Arca reticulata Gmelin, Syst. Nat., vi., p. 3311, 1792. Arca reticulata Chemnitz, Conch. Cab., vii., p. 193, pl. 54, fig. 540. Arca squamosa, domingensis et clathrata Lam., An. s. Vert., vi., pp. 35, 40, and 46, 1819. Arca gradata Brod. and Sby., Zool. Journ., iv., p. 365, 1829. Arca divaricata Sby., P. Z. S., 1833, p. 18 ; Reeve, Conch. Icon., Arca, pl. 16, fig. 108, 1844. Kocene of the Jacksonian at Moody’s Branch, Jackson, Mississippi; Oli- gocene of the Bowden beds, Jamaica; Matura, Trinidad; of the Tampa silex beds at Ballast Point, Florida, and on the Chipola River; Pliocene of Limon, Costa Rica, and of the Caloosahatchie marls; Pleistocene of the Antilles generally; and recent from Cape Hatteras to Barbadoes and the Gulf of Campeachy. The fossils are identical with the recent shells in every particular, and there can be no doubt that this species has existed continuously in the An- tillean region since the Upper Eocene. Section Fossudarca Cossmann. Barbatia (Fossularca) Adamsi (Shuttleworth) Smith. Arca c@lata Conrad, Fos. Medial Tert., p. 61, pl. 32, fig.2, 1845; not of Reeve, Conch. Icon., 1844. Arca lactea C. B. Adams, not of Linné. Arca Adamsi Shuttlew. (MS.), Smith, Jour. Lin. Soc. Zool., vol. xx., p. 499, pl. 30, figs. 6, 6a, 1888. Dall, Bull. Mus. Comp. Zool., xii., p. 243, 1886. Oligocene of the Bowden beds, Jamaica, of the Chipola River and Oak Grove, Florida; Miocene of Duplin County, North Carolina; Pliocene marls of the Caloosahatchie, Shell Creek, and Alligator Creek, Florida, and the Waccamaw River, South Carolina. Recent, with a range from Cape Hatteras, North Carolina, to the island Fernando Noronha, on the coast of Brazil, in five to one hundred and sixteen fathoms. This species is well distiMguished from the similar looking A. /actea of Europe by the fact that its radial riblets are formed by rows of trailing blis- ters or hollow flutings, which are very friable and often entirely worn off, TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA leaving the shell practically smooth. Though the shell has long been labelled with Shuttleworth’s name in collections, the first published description I have met with is that of Mr. E. A. Smith, above referred to. Conrad’s specific name is preoccupied. The fossils agree exactly with the living specimens, except that those from the Oligocene are usually somewhat smaller than the full-grown recent shells. Barbatia (Fossularea ?) ovalina n. s. PLATE 32, Ficure 18. Oligocene marl of Bowden, Jamaica; rare; Henderson and Simpson. Shell minute, solid, ovate, with rather inflated valves; beaks low in the anterior fourth, prosogyrate; cardinal area short, narrow, smooth, or longi- tudinally striate, the part occupied by the ligament forming a small excavated triangle with the apex at the beak in each valve; surface nearly smooth, sculpture of faint, irregular, concentric lines, crossed by still fainter sparse radiations which are not pronounced enough to modify the surface; inner margin of valves smooth; muscular impressions large; hinge short with about three crowded anterior and four oblique posterior teeth, the two series separated by a wide gap below the ligament. Lon. 3.2, alt. 2.5, diam. 2 mm. A single specimen of this curious little shell, with the form of a Wuczula, the cardinal margin of a Limopsis, and the teeth of an Arca, was found in the marl. It should, perhaps, be referred to Lzssarca Smith. Section Cucullayia Conrad. 2 Barbatia (Cucullaria) Aldrichi n. s. PLATE 32, FIGURE 19. Claiborne sands, Claiborne, Alabama; Burns. Shell small, elongate, thin, somewhat pointed behind, rounded in front, moderately convex, with low, prosogyrate beaks; cardinal area very narrow and elongated, widest in front of the beaks; surface evenly sculptured by fine equal, flattish radial riblets, separated by narrower grooves and crossed by irregularly spaced impressed lines; inner margin of the valves smooth or slightly fluted in harmony with the ribs, especially behind; beaks in the anterior fourth; hinge-line about two-thirds the length of the shell; hinge anteriorly with four oblique, rather close-set teeth, separated by a wide gap from the posterior teeth, which are about six in number, smaller proximally, and parallel with the hinge-line. Lon. 8.3, alt. 5, diam. 4 mm. FREE INSTITUTE OF SCIENCE 631 TERTIARY FAUNA OF FLORIDA 2) A single specimen of this interesting shell was obtained, adding a new eroup to the list of Eocene forms found in the Claibornian. The hinge is somewhat like that of Arca (Cucullaria) Caillati Deshayes, but wants the central vertical denticles. The form is more like that of A. gracilis Desh., but wider and more regular. Barbatia (Cucullaria) taniata n. s. PLATE 25, FIGURE I, Ia. Pliocene marls of the Caloosahatchie and Shell Creek, Florida, Dall and Willcox, and of the Croatan beds of North Carolina, at Mrs. Guion’s marl pit, C. W. Johnson. Shell thin, elongated, arcuate, mesially compressed, in general inflated ; the beaks near the anterior fifth; anterior end rounded, short; posterior higher, produced, and bent down; base receding mesially ; cardinal area short and wide in front of the beaks, long and narrow behind them, in front smooth or longitudinally striated, behind with a few oblique grooves; sculpture of small, flat, radial ribs arranged in pairs with narrower interspaces, and between every set of two pairs and the next a wider interspace, as if the ribs were quadripartite ; these ribs cover all the shell, more sparsely on the posterior dorsal slope, and are crossed at wide but not perfectly regular intervals by narrow, flat, concentric ridges; inner margin of the valves smooth, except when modified by the external ribbing; hinge two-thirds as long as the shell, with four rather large oblique anterior teeth separated by a wide edentulous gap from a row of about twenty short vertical teeth, which merge into a group of six or seven oblique posterior teeth, becoming larger distally ; the extreme distal teeth in full-grown specimens sometimes break up into irregu- lar granules. Length of adult shell 52, of hinge-line 20, alt. of shell 23, diam. 21 mm. Subgenus NOETIA Gray. Arca (Noétia) limula Conrad. PLATE 31, FIGURES 14, 140. Arca limula Conr., Fos. Tert. Form., p. 15, pl. 1, fig. 1, 1832. New Berne, North Carolina. Miocene: North Carolina, at Wilmington, New Berne; Virginia, at various points on the York and James Rivers; also in Maryland and South Carolina, and at Heislerville, Cumberland County, New Jersey. Pliocene: De Leon Springs, Florida, Wright; in the marls of the Caloosahatchie and TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA 632 Shell Creek, Willcox and Dall; near Brunswick, Georgia, Couper; Wacca- maw beds, South Carolina, C. W. Johnson. Arca limula var. platyura Dall. Pliocene of the Caloosahatchie and Alligator Creek ; Willcox and Dall. Shell with the posterior end of the cardinal border elevated and forming nearly a right angle with the posterior margin of the valves, thus giving the posterior part of the shell a higher and more angular look, which at first seems very distinct. Area limula var. filosa Conrad. Noétia ponderosa Say, var. N. carolinensis Conr., Proc. Acad. Nat. Sci. Phila. for 1862, p- 290; not Arca carolinensis Wagner, 1847. Arca carolinensis Heilprin, Proc. Acad. Nat. Sci. Phila. for 1881, p. 450. Noétia filosa Conrad, Kerr's Geol. Rep. N. Car., App. A, p. 20, pl. 4, fig. 3, 1875. Miocene of North Carolina: at Sullivan’s marl-pit, Green County, North Carolina, eight miles east of Snow Hill; Burns. This variety has more numerous (thirty-five) ribs when adult and a less angular outline than the typical form. Arca limula is, with little doubt, the progenitor of A. ponderosa Say, from which it differs by a more quadrate outline and more anterior beaks. The sculpture is usually more elegant, but specimens of A. ponderosa occasion- ally turn up which exhibit equally fine reticulation and divarication of the ribs. A variety analogous to platyuwra is possessed by all the species of Noétia, but is perhaps more conspicuous in A. Zula. I have not found this species in any positively Post-Pliocene beds; in such it is represented by A. ponderosa. From A. zucile, when adult, A. “mula is distinguished by its smaller and shorter cardinal area and usually by its considerably larger size; the line of teeth is shorter and the teeth are larger and wider, and more horizontally extended at the ends of the series. Arca (Noétia) incile Say. Arca inctle Say, Journ. Acad. Nat. Sci. Phila., 1st Ser., iv., p. 139, pl. 10, fig. 3, 1824. Miocene of Maryland. Conr., Fos. Tert. Form., p. 16, pl. 2, fig. 1, 1832; Fos. Medial Tert., p. 56, pl. 29, fig. 5, 1840. James River and Smithfield, Virginia. Noétia protexta Conr., Kerr's Geol. Rep. N. Car., App. A, p. 19, pl. 3, fig. 5, 1875. Miocene of North Carolina. FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA OD ios) Ww Miocene of Maryland, Virginia, and North Carolina, Say and Conrad; near Darlington, South Carolina, at various points near and at the Natural Well, Duplin County, North Carolina; Petersburg, Dinwiddie, York River, and borders of the Dismal Swamp, Virginia, and Choptank, Maryland, Harris, Burns, and others. There can be no doubt that Conrad's WV. protexta is identical with A. incile. This species has not yet turned up in the Floridian Miocene, but a knowledge of it is necessary to discriminate between the species of Noécza. Arca (Noétia) ponderosa Say. Arca ponderosa Say, Journ. Acad. Nat. Sci. Phila., 1st Ser., il., p. 267, 1822. Recent in Florida. Arca contraria Reeve, Conch. Icon., Avca, pl. 8, fig. 55, 1844. Arca elegans, Phil. Zeitschr. Mal., 1847, p. 92. Arca ponderosa Tryon, Am. Mar. Conch., p. 178, pl. 36, figs. 467-8, 1874. Pleistocene of Cape May and Atlantic City, New Jersey; of Maryland, near Cornfield Harbor, at Wailes Bluff, on the Potomac River; of Simmons Bluff, South Carolina; and many points on the coast of Florida; recent on the eastern coasts of North America from Cape Cod to Yucatan. This is the type of the subgenus. In this species the beaks are more nearly in the middle of the shell than in either of the others. The ligament does not occupy the whole of the cardinal area, and the greater portion of it is in front of the beaks and strongly transversely striated. The borders of the adductor scars are sometimes marked by an elevated ridge as strong as in many Cuculleas. It is curious that Conrad should state (Proc. Acad. Nat. Sci., 1862, p. 290) that he had not seen a recent specimen of this species, and that he supposed it to be extinct. It is probable that he was thinking of A. Zenosa Say when he recorded these remarks, as the present species is almost the commonest recent species of our shores. There can be little or no doubt that the names of Reeve and Philippi are based on young specimens of this somewhat variable shell. Subgenus SCAPHARCA Gray. Section Ciumearca Dall. Scapharea (Cunearca) cumanensis Dall. Arca incongrua Guppy, Proc. Sci. Assoc., Trinidad, p. 163, Dec., 1867; Geol. Mag., Dec., 1874, p. 451; not of Say. TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA Oligocene of Cumana, Venezuela, Guppy; island in Lake Henriquillo, St. Domingo, Rowell. Shell small, resembling S. zzcongruwa Say in miniature, but with higher, more prominent, and uncompressed beaks, with the ribs of the posterior slope of the right valve smooth instead of nodulose; the valve higher and shorter, with the beaks more anterior, and the hinge-line somewhat shorter. Lon. of adult shell 26, alt. 25, diam. 21 mm. With a rather close general resemblance to A. zxcongrua Say, this little species differs in details, which, taken in connection with the great disparity in size and the geological horizon, authorize us to regard it as distinct. Scapharea (Cunearca) initiator n. s. PLATE 32, FIGURE II. Oligocene of the Chipola beds, Chipola River, Florida; Burns. Shell small, solid, oblique, with prosogyrate beaks, somewhat impressed mesially near the apices of the valves; right valve ovate-rhombic with twenty strong, rounded, nodulous, radial ribs, separated by wider interspaces; left valve decidedly smaller, with the ribs smooth, squarish, and without nodules, except a few on some of the shorter anterior ribs; cardinal area wider in front of the beaks, narrower behind them; margins of the valves internally fluted ; hinge-line short, with about twenty-two subequal vertical teeth. Lon. (of left valve) 5, alt. 4.7, diam. 5 mm. This little shell was at first thought to be the young of a larger species, but nothing allied to it of a larger size has turned up at any locality in the formation, while its solidity gives it a mature appearance. The cardinal area differs in form from any of the known species in the adult state. Scapharea (Cunearca) scalaris Conrad. Arca scalaris Conr., Proc. Acad. Nat. Sci. Phila., i., p. 324, 1843; Fos. Medial Tert., p- 59, pl. 31, fig. 1, 1845; Emmons, Geol. N. Car., p. 285, 1858; Tuomey and Holmes, Pleiocene Fos. S. Car., p. 43, pl. 16, fig. 1, 1856. Miocene of Petersburg, Virginia, Tuomey; of Duplin County, North Carolina, Burns, and of the upper bed at Alum Bluff, Florida, Dall. This species is doubtless the ancestor of S. sca/aviva Heilprin, the young of which it much resembles, though sufficiently distinct from the adult. Scapharea (Cunearea) scalarina Heilprin. Arca scalavina Hp., Trans. Wagner Inst., i., p. 94, pl. 12, fig. 29, 1887. FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA ¥ 635 Pliocene marls of the Caloosahatchie, Florida; Heilprin, Willcox, and Dall. This magnificent species is the largest and most distinct of the entire group, and so far has been obtained only on the Caloosahatchie River. The S. mcongrua has not yet been found in these marls. Scapharea (Cunearca) incongrua Say. Arca incongrua Say, Journ, Acad. Nat. Sci. Phila., ii, p. 268, 1822; Reeve, Conch. Icon., Arca, pl. viii., fig. 50, 1844. Not Arca braziliana Reeve, Conch. Icon., Avca, pl. i., fig. 17, 1844, = A. nodosa Wood. ? Arca braziliana Lam., An. s. Vert., vi., p. 44, 1819; Philippi, Abbild. u. Beschr., i., Arca, p. 2, pl. 1, fig. 3, 1843. Upper Miocene of the Galveston artesian well (?), Singley; Pliocene of Port Limon, Costa Rica, Gabb; typical specimens from Pleistocene of Wailes Bluff, Maryland, Simmons Bluff, South Carolina, Burns, and Brunswick, Georgia, Couper; recent from North Carolina south to Texas, and (var.? braziliana) from Texas south and east to Cape Roque and south to Rio, Rio Grande do Sul, San Paulo, and Santa Caterina, Brazil (Ihering). This species is a very puzzling one, and a large geographical series is required to determine its exact limits. The figure given by Reeve is poor, and has probably helped to continue the confusion. The typical A. zxcongrua is quite variable in form, and I have not seen specimens which could be unhesitatingly referred to it from older beds than the Pleistocene, or more southern localities, living, than the coast of Texas. Here it is mixed with specimens of the drazzlana type, towards which the imcongrua tends to vary. The Costa Rica Pliocene fossils are exactly like brazitana ; the Antillean shells also, while varying a good deal, retain the dimensions of éraz¢ana and more or less of its other characters. It is probable that the two forms would better be kept apart, at least until more is known. Scapharea (Cunearca) alcima Dall n. s. PLATE 31, FIGURES 5, 7. Pliocene marls of the Caloosahatchie at Alligator Creek, Florida; Dall. Shell of moderate size, short, high, inflated, with elevated prosogyrate beaks ; left valve with thirty strong, squarely nodulous, radial ribs somewhat narrower than the interspaces, without obvious concentric sculpture, front edge rounded, posterior less rounded and longer, meeting the base at a rather TRANSACTIONS OF WAGNER 636 TERTIARY FAUNA OF FLORIDA blunt angle, this part of the shell being somewhat produced; right valve with twenty-seven less prominent ribs, of which the posterior dozen have the nodules obsolete or absent and those on the anterior ribs somewhat less marked than on the other valve; cardinal area short, wide, with the beaks incurved over it; inner margin of the valves sharply fluted; hinge-teeth slightly larger and more oblique distally, in general nearly vertical, close set, and about thirty-two in number, not obviously divided in the centre. Lon. 27, alt. 27, diam. 22 mm.; lon. of hinge-line 15 mm. This is one of those species on the border-line of groups which make it so difficult to divide the Arks into clear-cut sections ; it has the hinge, cardi- nal area, and discrepant sculpture of Cunearca ; the valves are slightly unequal, and it seems most properly assigned to a place in this section. It is obviously a form ancestral to such species as Arca Chemnitzt Phil. (A. bicops Orb., + A. antillarum Dunker, fide Kobelt, + A. Orbignyi Kobelt), which is referred to Anomalocardia (= Anadara) by Ihering, and is found recent in the West S Indies. This species, which has been distributed under the (MS. ?) name of A. rhombica Rawson, is also inequivalve, with discrepant sculpture, and prob- ably should be referred to this section. From A. Chemnitzi the present species differs by its larger size, more oblique shape, narrower and more numerous ribs. Arca filicata Guppy from the Eocene beds of Manzanilla, Trinidad, is probably, though much smaller, a precursor of the above-mentioned species. Section Scapharca s. s. Scapharea (Scapharca) lienosa Say. Arca lienosa Say, Am. Conch., iv., pl. 36, fig. 1, 1832; Tuomey and Holmes, Pleioc. Fos. S.’Car., p. 40, pl. 15, figs. 2, 3, 1855; Emmons, Geol. N. Car., p. 284, fig. 204; 1858. Scapharca licnosa Meek, Smithsonian Checkl. Miocene Fos., p. 6, 1864. Arca floridana Heilprin, Trans. Wagner Inst., i., p. 97, 1887 ; not of Conrad, Am. Journ. Conch., v., p. 108, pl. 12, fig. 2, 1869 (as Anomalocardia) = A. secticostata Rve., Icon., fig. 38, 1844. Miocene of York and James River, Virginia, of Wilmington and Duplin County, North Carolina, and of the upper bed at Alum Bluff, Florida; Plio- cene of the Waccamaw District, South Carolina, the Caloosahatchie River, Alligator and Shell Creeks, Florida; Tuomey, Burns, Willcox, and Dall. Not known in the recent state. FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA This species has always been rather rare, and has been confounded with its undoubted descendant, the Arca floridana of Conrad, found living in Florida waters. Nevertheless, the recent and the fossil shells are readily dis- tinguished on comparison. It is probable that the rarity of the living shell has prevented the comparisons being made. This species had previously been named secticostata by Reeve, from a specimen of which the habitat was unknown. This name, of course, will have to be adopted. In A. Lenosa there are about forty ribs in a specimen one hundred and eight millimetres long; these ribs are deeply grooved down the centre, and the ridges on either side of the grooves are likewise longitudinally grooved with one or two incised lines. The interspaces between the ribs are narrower than the ribs; the beaks are less anterior than in A. secticostata. In the latter the ribs are much narrower than their interspaces, flat-topped, and distally for a little more than half their length in the adult the top of the rib has a broad, shallow channel. In no case are there any subsidiary grooves. Minute con- centric ridges are quite obvious in both species, but the fossil has the ridges more generally and conspicuously beaded. In other respects the shells are extremely similar. Scapharea (Scapharca) hypomela n. s. PLATE 33, FIGURE 1. Oligocene of the Ballast Point silex beds, Tampa Bay, of the lower bed at Alum Bluff, and of the Chipola marl, Chipola River, Florida. Shell of moderate size, long, inflated, with rather low, mesially com- pressed, prosogyrate beaks; left valve with about forty-three deeply chan- nelled, flat-topped ribs with fine, regular, concentric beading, except on the posterior slope, where the ribs are lower, flatter, and obsoletely channelled ; near the margin some of the ribs have a second set of finer grooves; hinge- line straight, anterior end descending vertically, then obliquely rounded into the base, which is nearly parallel with the hinge-line; the posterior end descends more obliquely and the basal angle is prolonged a little and rounded; the interspaces between the ribs in both valves are very narrow, and on the right valve the beading is less conspicuous; the cardinal area is somewhat concave, flattish, with three or four concentric grooves in lozenge form; teeth of the hinge similar, numerous, not interrupted, short, vertical, the distal teeth a little longer and more oblique ; margin of the valves fluted, the right valve slightly smaller than the other. Lon. 50, alt. 25, diam. 20 mm. TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA 638 This species has the appearance of being the Oligocene ancestor of the Miocene A. “enosa, from which it differs by its smaller size, closer and rather narrower ribbing. Scaphareca (Scapharca) latidentata n. s. PLATE 36, FIGURE I5. From the Oligocene of Ballast Point, Tampa Bay, of the lower bed at Alum Bluff, and in the Chipola marls of Florida, and probably from the Oak Grove sands in western Florida. Shell small, ovate, moderately convex, with low, quite anterior, mesially sulcate, prosoccelous beaks; left valve with about thirty rounded, radiating, undivided ribs, separated by slightly wider interspaces, and crossed by numerous smaller concentric ridges which become beadlike on the ribs and vary in prominence in different specimens; base evenly arcuate, ends rounded; cardinal area narrow, impressed, smooth, with one or two grooves behind the beaks, but none elsewhere; valves slightly twisted, so that the basal margin is not in a single plane; line of teeth interrupted a little behind the beaks, the anterior series having the anterior and posterior teeth larger and the intervening teeth thinner and more closely adjacent, all nearly vertical ; posterior teeth vertical, shorter, the series longer, the teeth smallest proxi- mally and regularly increasing in size towards the distal end of the series, equidistant and regular; inner margin of the valve deeply fluted. Lon. 18, height 11, diam. g mm. This little shell looks a good deal like the young of Anadara aresta Dall, but has the beaks less central, less prominent, and distinctly impressed mesially, giving a somewhat bilobed aspect to the very young. Scapharca (Scapharea) callicestosa n. s. PLATE 34, FIGURES 17, 18. Upper bed (Miocene) at Gaskin’s Wharf, on the Nansemond River, sixteen miles below Suffolk, Virginia; F. Burns. Shell of moderate size, rather thin, rhomboidal, with small, prominent, mediosulcate, prosoccelous beaks situated at about the anterior third of its length; left valve with about thirty-seven squarish subequal radial ribs, sepa- rated by narrower channelled interspaces; on the tops of these ribs are four longitudinal threads, the inner pair larger and more prominent but separated by a somewhat deeper sulcus than those external to the inner threads; con- centric sculpture of fine, close, rounded, slightly elevated threads, which over- FREE INSTITUTE OF SCIENCE 62 f 39 TERTIARY FAUNA OF FLORIDA run the whole shell, ribs, and interspaces, and at short intervals, at the inter- section with the inner pair of rib-threads, they become minutely nodulous, while the reticulations have a punctate appearance, giving a surface somewhat like fine lace and peculiar, as far as observed, to this species; cardinal area short, rather narrow, with sharply elevated boundaries and a single incised set of grooves forming a lozenge-shaped figure anteriorly ; hinge-line short, teeth in two adjacent series, anterior with fifteen, posterior with twenty-six or twenty-seven teeth set vertically, a little oblique at the distal ends of the series ; each individual tooth more or less grooved or striate in the direction of motion, as in some recent species; anterior end of shell produced, rounded; posterior end subtruncate, base slightly arched; inner margin of the valves with rather long, deep flutings, corresponding to the external ribs. Lon. 32, alt. 27, diam. 20 mm. (twice the diameter of the single valve). A single valve of this very elegant species was obtained by Mr. Burns. Its sculpture differentiates it from all our other Tertiary species. Arca calli- pleura Conrad, in which the ribs have a minute nodular sculpture, has the radial threading predominant, while in this species the concentric threads over- run all the rest. The two species are entirely distinct otherwise. Scapharca (Scapharca) idonea Conrad. Arca tdonea Conrad, Fos. Tert. Form., p. 16, pl. 1, fig. 5, 1832. Arca stillicidium Conrad, op. cit., p. 15, pl. 1, fig. 5 (young shell). Arca idonea Conrad, Fos. Med. Tert., p. 55, pl. 29, fig. 3, 1840. Scapharca tdonea Conrad, Proc. Acad. Nat. Sci. Phila. for 1862, p. 579, 1863. The typical form has twenty-five ribs, and has been obtained from the Miocene of St. Mary’s River, Maryland, and the upper bed at Alum Bluff, Florida. The more elongated variety, with thirty-one ribs, figured in the Medial Tertiary, is also found at St. Mary’s, at Windmill Point, and in Surry County, Virginia, and in the Miocene of Alum Bluff, Florida. A somewhat more angular type than either of the above is obtained from the Miocene of St. Mary’s River, Maryland. The species is one of the most abundant and finest of the Chesapeake Miocene. Scapharea (Scapharea) carolinensis Waener. PLATE 33, FIGURE II. Arca carolinensis Wagner, Trans. Wagner Inst., v., p. 9, pl. 1, fig. 4; Bronn, Index Pal. Nom., p. 93, 1848 ; Syst., p. 283, 1849. TRANSACTIONS OF WAGNER 640 TERTIARY FAUNA OF FLORIDA ‘ Miocene of North Carolina? Wagner; of York River, Virginia, station 2250, Harris; of Duplin County, North Carolina (young), Burns. Shell large, solid, squarish, moderately inflated, with subcentral, proso- ccelous, rather elevated beaks; left valve with about thirty ribs, with subequal interspaces, the anterior ribs squarish, with a shallow median sulcus near the margin, and irregular concentric ripples; the ribs of the middle of the valve not sulcate, with less rippling, more closely adjacent, the interspaces very squarely channelled; the posterior ribs smaller, rounded, and more closely set; cardinal area short, rather wide, smooth, or longitudinally striate, with three concentric lozenge-shaped groovings; hinge-line short, solid; the teeth not interrupted, strong, about forty-five in all, the anterior more vertical, the middle teeth inclining towards the middle line of the area, the posterior teeth distally, more oblique and longer; margins of the shell strongly fluted. Lon. 56, alt. 55, diam. 43 mm. (type specimen). As this species seems never to have been described, the references in Bronn being merely to Wagner’s unpublished plates, I have given a diagnosis from Professor Wagner’s original type specimen, and refigured the interior of the left valve. The shell is remarkable for its squarish form, which is rather distantly approached by some specimens of A. zdonea. It is singular that in all the years which have elapsed since this shell was collected and figured by Professor Wagner no one has recognized or described it. Scaphareca (Scapharca) dodona n. s. PLATE 31, Ficures 1, 8, 8a. Oligocene marl of Oak Grove, Santa Rosa County, Florida; Burns. Shell small, solid, inequilateral, inflated, and rounded in front, pointed and attenuated behind; with mesially impressed, prosoccelous beaks; left valve with thirty-six squarish radial ribs, each with a deep central groove longitu- dinally, the portions on each side with a shallower longitudinal sulcus, so that each rib, except in young shells, is composed of four threads set in two pairs; the ribs separated from each other by channelled interspaces about half as wide as the ribs ; concentric sculpture of numerous rather close set, regu- lar, blunt, elevated lines, which appear on the riblets as fine undulations ; beaks at the anterior third; cardinal area, with a raised margin, lozenge-shaped, rather wide, slightly narrower behind the beaks, with about four rather wavy sets of concentric grooves; hinge-line short, solid, the teeth not interrupted, larger distally, the most anterior tending to break up into granulations, about FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA On fifty in all, subvertical, shorter in the middle of the hinge; margins of the valve deeply fluted; right valve with wider interspaces and narrower, often tripartite, ribs. Lon. 40, alt. 28, diam. 30 mm. This fine shell has a neat and elegant surface sculpture, and is one of several which the Oak Grove marl contains and which appear to be new. Scapharea (Scapharca) santarosana n. s. PLATE 31, FIGURES 2, IO. Oligocene of the Chipola River marl, of the lower bed at Alum Bluff, of the Sopchoppy limestone, and of the Oak Grove sands, Santa Rosa County, Florida; Burns and Dall. Shell small, short, plump, rostrate, with moderately elevated, mesially sulcate prosoccelous beaks; left valve with thirty elevated, squarish, radial ribs, separated by slightly narrower channelled interspaces; the ribs on the posterior slope are low, smaller, and nearly smooth; those on the middle of the shell have mostly near the margin a shallow mesial sulcus; in those still more anterior the sulcus is deeper and wider, dividing each rib over most of its length into two more or less rounded riblets; concentric sculpture of regu- larly spaced elevated lines, which on the ribs appear as prominent ripples; right valve having the ribs narrower and less strongly sculptured, and the sulci less distinct ; cardinal area short, with about three concentric grooves ; beaks within the anterior fourth; hinge-line short, with about fifty-seven rather irregular, closely adjacent, nearly vertical teeth, longer and more oblique dis- tally; margins strongly fluted; base flexuous, posterior end narrow, pointed, without any marked angle at the end of the hinge-line. Lon. 36.5, alt. 28, diam. 28 mm. This species is most nearly related to A. staminata Dall, from which it can be distinguished especially by its lower beaks, more oblique posterior slope, more flexuous base, and attenuated posterior end. Scapharea (Scapharca) staminata n. s. PLATE 31, FIGURES II, 13. Oligocene of the lower bed at Alum Bluff, and perhaps at Roberts, Escambia County, Florida. Shell of moderate size, plump, rhombic, with well-elevated, hardly sulcate, slightly prosoccelous beaks, situated in the anterior third of the length ; left valve with twenty-eight or twenty-nine radial ribs, the posterior of TRANSACTIONS OF WAGNER 642 TERTIARY FAUNA OF FLORIDA which are smooth and almost rounded; those on the middle of the valve are squarish, with wider channelled interspaces, and rippled or furnished with transverse nodulation above, which grows stronger and more crowded ante- riorly ; the ribs are not sulcate or dichotomous, and hardly differ on the two valves; hinge-line straight, rather long, and with conspicuous angles at the ends; anterior end of the valve rounded, base nearly parallel with the hinge- line, posterior end somewhat produced; beaks narrow, cardinal area with from three to five sets of lozenge-shaped groovings; hinge strong, the teeth in two adjacent series, somewhat oblique, smaller mesially, at the anterior end of the hinge sometimes more or less broken into granules; inner margin of the valves fluted, interior radially striate. Lon. of a large valve 47, alt. 37 mm.; lon. of figured shell 39, alt. 30, diam. 28 mm. This species differs from A. santarosana, which occurs in the same beds, by its more rhombic form, proportionately longer hinge-line, and unsulcate ribs. It is also a larger and less elegantly sculptured shell. A. stamcnea Say, of which s¢taminata may prove to be an Oligocene race, has a proportion- ately longer hinge-line, is more sharply truncate behind, and more obliquely rounded in front, the beaks are less elevated and wider, the ribs anteriorly are only sparsely and feebly nodular, while the aspect of the whole shell is less elegant. Scapharea (Scapharea) staminea Say. Arca staminea Say, Am. Conch., iv., pl. 36, fig. 2, 1832. Arca elevata Conrad, Fos. Med. Tert., No. 1, cover, 1840. Arca trigquetra Conrad, Proc. Acad. Nat. Sci. Phila., i., p. 305, 1843; Fos. Med. Tert., p- 59, pl. 31, fig. 2, 1845. Scapharca triguetra Conrad, Proc. Acad. Nat. Sci. Phila. for 1862, p. 580, 1863. Miocene of Calvert Cliffs, Choptank River, and Jones’s Wharf, near Cen- treville, Maryland; of York River, Virginia, and Walton County, Florida; Say, Burns, Harris, and Johnson. The differences between this and A. staminata are detailed under that species. Scapharea (Scapharea) chiriquiensis Gabb. A. chiriguiensis Gabb, Proc. Acad. Nat. Sci. Phila., xii., p. 567, 1861. Oligocene of Chiriqui, Central America, and of an island in Lake Henri- quillo, St. Domingo; Gabb and Rowell. The absurdity of referring this species to A. grandis Broderip is evident on a comparison, and the A. patricia of Sowerby (Quart. Journ. Geol. Soc. FREE INSTITUTE OF SCIENCE re : 643 TERTIARY FAUNA OF FLORIDA London, vi., p. 52,1850) not being figured, the number of ribs and the pro- portional measurements being omitted from Sowerby’s diagnosis, can hardly be identified, though it probably resembles this species, which has about thirty rounded ribs with subequal channelled interspaces, the anterior ribs being granulose or nodiferous, the shell remarkably high, short, solid, and wide. The measurements of a well-grown specimen are: alt. 42, lon. 45, and diam. 44 mm.; the length of the cardinal area is 28 mm. It is one of the species on the border line between Scapharca and Anadara, the two valves being similarly sculptured and almost equal. Scapharea (Scapharca) Lesueuri Dall. Lesueur, Walnut Hills Fos., pl. v., fig. 8, 1829. Arca mississippiensis Conrad, Journ. Acad. Nat. Sci. Phila., 2d Ser., i., p. 125, pl. 13, figs. 11, 15 ; Proc. Acad. Nat. Sci. Phila., iii., p. 294, 1848. Not Byssoarca mississippiensts €onrad, Journ. Acad. I. c., p. 125, pl. 1, fig. 323. Anomalocardia mississippiensis Conrad, Am. Journ. Conch., 1., p. 11, 1865. Not Cucullearca mississippiensis Conrad, Am. Journ. Conch., i., p. 11, 1865. Vicksburgian Oligocene of Mississippi. It is obvious that the same specific name cannot be used twice in the same genus for a valid species, and so I have proposed to call the present one Arca Lesueuri, in honor of the excellent naturalist who was the first to call attention to it. Scapharea (Scaphareca) arata Say. Arca arata Say, Journ. Acad. Nat. Sci. Phila., rst Ser., iv., p. 137, pl. 10, fig. 1, 1824 ; Conrad, Fos. Med. Tert., No. 3, p. 58, pl. 30, fig. 6, 1845. Miocene of St. Mary’s County, Maryland; Burns. This species is the oldest of the group to which it belongs, which includes A. improcera, A. buccula, A. plicatura, etc., and which is represented in the recent fauna by A. transversa Say. Scapharea (Scapharea) improcera Conrad. Arca improcera Conrad, Fos. Med. Tert., p. 60, pl. 31, fig. 5, 1845. Scapharca improcera Conrad, Proc. Acad. Nat. Sci. Phila. for 1862, p. 579, 1863. Arca plicatura (juvenis) Heilprin, Proc. Acad. Nat. Sci. Phila. for 1881, p. 451. Upper Miocene of Warwick, Virginia; of Duplin County and Wil- mington, North Carolina; of Timminsville and Darlington, South Carolina, Burns; Pliocene of the Caloosahatchie River and Shell Creek, Florida, Dall and Willcox. TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA 644 This shell should not, in my opinion, be united with A. plicatura, as has been done by Heilprin. When properly discriminated it is a smaller and more rhombical shell, with lower and more anterior beaks, and more produced and pointed posterior end; the base and hinge-line are nearly parallel, and the latter is narrower in specimens of the same size than in A. plicatura. Both have about thirty-five ribs, but in A. zzprocera these are plain, while in A, plicatura the anterior ribs are prettily nodulous. Arca buccula Conrad (Fos. Med. Tert., p. 60, pl. 31, fig. 4) appears to be a short, heavy, stunted, and abnormally thickened variety of this species, such as might be produced by an unfavorable environment. It is confined to the Upper Miocene marls of Duplin County, North Carolina. Scapharca (Scapharca) plicatura Conrad. Arca plicatura Conrad, Fos. Med. Tert., p. 61, pl. 32, fig. 4, 1845; Heilprin, Proc. Acad. Nat. Sci. Phila. for 1881, p. 451, ex parte. Arca lineolata Conrad, Fos. Med. Tert., p. 61, pl. 32, fig. 3, 1845; not of Roemer, 1836. Arca sublineolata Orbigny, Prodr. Pal., iii., p. 125. Arca eguicostata Conrad, Fos. Med Tert., p. 60, pl. 31, fig. 6, 1845; Tuomey and Holmes (?), Pleioc. Fos. S. Car., p. 44, pl. 16, figs. 3, 4, 1856. Arca brevidesma Conrad, Fos. Med. Tert., p. 62, pl. 32, fig. 5, 1845. Upper Miocene of Duplin County, North Carolina, of the Sumter Dis- trict, South Carolina, and of De Leon Springs, Florida; Pliocene of the Waccamaw beds of South Carolina; Burns and Johnson. This is a considerably larger species than A. zwzprocera, more rounded and with a tendency to nodulation of the ribs. I am somewhat doubtful if the shell figured by Tuomey and Holmes is to be identified with it. It has a very close resemblance to A. avata Say, and is much larger than any specimens of plicatura 1 have seen. The sculpture of the two valves in plicatura is markedly discrepant, which is not the case in zmprocera, In this, the former more nearly approaches A. transversa, but the latter has reverted to the rhombical form of 7¢zprocera. Scapharea (Scapharca) campyla n. s. PLATE 31, FicuRES 3, 4; PLATE 32, FIGURE 22. Pliocene of the Caloosahatchie, Shell Creek, Alligator Creek, and Myakka River, Florida; Willcox and Dall. Shell of moderate size, solid, rather rude, the posterior end strongly twisted to the right, the beaks low, and the form somewhat compressed; the FREE INSTITUTE OF SCIENCE Hea 645 TERTIARY FAUNA OF FLORIDA umbones are very slightly bent forward, and are situated at about the anterior third; left valve with about thirty low, flat radial ribs, becoming wider and sparser posteriorly, crossed by rather rude incremental lines, but not nodulous or dichotomous, and with subequal, rather shallow channelled interspaces ; the right valve is similarly sculptured and somewhat smaller; cardinal area rather long, narrow, with numerous slightly angular, longitudinal grooves ; ends of the hinge-line moderately angular, anterior end of shell rounded, posterior produced, base flexuous, inner margins fluted; teeth numerous, small, uninterrupted, nearly vertical, the distal ones larger and tending to break up into granules. Lon. of a large valve 50, alt. 34 mm.; of figured specimen, lon. 38, alt. 27, diam. 20 mm. This species is one of the most abundant in the Floridian Pliocene, and is easily distinguished from any other by its compressed appearance and twisted shape. Some of the allied species have a slight flexuosity, but in none is this feature so pronounced as in A. campyla. A variety with thinner shell and narrower and slightly more elevated ribs was at first thought to be distinct, and may be named var. eretea. It is figured plate 32, figure 22. Scapharca (Scapharca) subsinuata Conrad. Arca subsinuata Conrad, Fos. Med. Tert., p. 62, pl. 32, fig. 6, 1845. Pliocene of the Croatan beds, near New Berne, North Carolina. I have seen only one specimen of this shell, which was identified by Conrad and has been many years in the National collection. It is very close to A. avata Say, from which the individual referred to differs chiefly by having two or three more ribs, and in being somewhat less angular at the posterior end of the hinge-line. A good series would probably connect them. A species near to this is represented in the Upper Miocene fauna of the deep artesian well at Galveston, Texas, but the specimens are too young to be specifically identified. Scapharea (Scapharea) transversa Say. Arca transversa Say, Journ. Acad. Nat. Sci. Phila., ist Ser., ii., p. 169, 1822; Conrad, Fos. Tert. Form., p. 15, pl. 1, fig. 2, 1832; Tuomey and Holmes, Pleioc. Fos. S. Car., p. 42, pl. 15, fig. 6, 7, 1856; Emmons, Rep. Geol. N. Car., p. 285, 1858. Pliocene of Myakka River and De Land, Florida; Pleistocene of North Creek, Little Sarasota Bay, Florida; of Simmons Bluff, South Carolina, Wailes Bluff, Maryland, and Sconset, Rhode Island. Recent from Cape Cod TRANSACTIONS OF WAGNER 646 TERTIARY FAUNA OF FLORIDA south to Key West, Florida, and southwest to Vera Cruz and the Gulf of Campeachy, Mexico, in shallow water. This is not the Arca transversa of Portlock (1843), nor of Rogers (Dec., 1839). The latter, a Cvezllea, has been renamed A. (C.) Rogersiana by Nyst (Tabl. Synopt. Arcacées, p. 63, 1848), and A. (C_) Rogers by Heilprin (Proc. Acad. Nat. Sci. Phila. for 1881, p. 449). This species has the rounded nodulous ribs and discrepantly sculptured valves of A. plicatura, with the more rhombic form and solidity of A. ampro- cera, with both of which it is doubtless genetically connected. It is not known below the Upper Pliocene. Scapharea (Scapharca) halidonata n. s. PLATE 33, FIGURE 24. Oligocene of the Bowden beds, Jamaica, and of Curagao; Henderson, Simpson, etc. ; Shell subequivalve, ovate, oblique, inflated; beaks rather high, strongly bent forward, almost reaching the anterior fourth of the length; left valve larger, with about thirty-four clear-cut, elegantly sculptured radial ribs; the anterior dozen ribs are usually dichotomous or deeply sulcate; the ribs on the middle of the shell-are grooved with one or two shallow, sharp, incised lines; the more posterior ribs are wider and flatter with three or more grooves; those on the posterior dorsal slope are angular, narrower, and usually have not more than one groove, which is nearly obsolete; the con- centric sculpture is of evenly spaced, fine, elevated lines arched in the inter- spaces and finely nodulating the anterior ribs; the sculpture is similar on both valves; the anterior end of the shell is rounded, the base arcuate, the posterior end oblique above and produced below; the ends of the hinge-line are angulated; the cardinal area is moderately wide with about three concen- tric lozenges outlined by the grooving; the hinge-line is straight, the teeth numerous and mostly vertical, the two series not interrupted, the posterior distal teeth tending to become irregular in the adult. Lon. of shell 55, of hinge-line 41, alt. 40, diam. 40 mm.; large specimens reach a length of 68 mm. This shell is usually named A. consobrina Sby. in collections, but when compared with the excellent figure of the St. Domingo species given by Sowerby, it is evident the two cannot be united. Sowerby’s species is more elongated, with a much straighter base, the beaks smaller and lower, and the height of the shell proportionately much less than in A. haldonata. FREE INSTITUTE OF SCIENCE Belen ee i 647 TERTIARY FAUNA OF FLORIDA Moreover, the name cozsobrina had been used by d’Orbigny six years earlier for a French fossil species, and was therefore not available for the West Indian fossil. Sowerby’s diagnosis is not distinctive and would apply equally well to several species. A. zncquilatcralis Guppy, from Bowden, is more like his figure than is the present species. There are in the Oligocene rocks of Gatun and other localities on the Isthmus of Darien, near Panama, several species of Avca of which I have imperfect specimens, some of which are nearly allied and may prove identical with A. halidonata. The A. consobrina of Guppy’s papers is the present species, which was erroneously referred to A. floridana Conr. by Gabb. Scapharea (Scapharca) inequilateralis Guppy. Arca inequilateralis Guppy, Quart. Journ. Geol. Soc. Lond., xxii., p. 293, pl. xviii, fig. 2, 1866. Oligocene of the marls of Bowden, Jamaica ; Guppy, Henderson, and Simpson. This species is closely related to A. latzdentata Dall, of the Chipola, Florida, Oligocene marls, but may be distinguished from it at once by the shorter, more delicate, and much more numerous hinge-teeth of the Jamaica shell. The latter is also thinner and more elegant in sculpture and less inflated. It somewhat resembles the young of A. hypomela Dall and A. floridana. Scapharea (Scapharca) actinophora n. s. PLATE 33, FIGURE 26. Shell subequivalve, ovate, moderately inflated, attenuated behind; beaks low, mesially impressed, much bent forward, situated in the anterior fourth of the length; left valve slightly larger, with about forty squarish, uniform, entire radial ribs, with narrower channelled interspaces, the ribs slightly flatter and wider distally; transverse sculpture of fine, low, equidistant, sub- equal, rather close-set elevated lines which are concavely arched as they pass over the ribs; sculpture nearly identical on both valves; hinge-line long, straight, anterior end nearly a right angle, the valve margin evenly rounded to the arcuate base; posterior end narrower, produced; cardinal area lanceolate, wider in front, with six or seven concentric grooves, angular near the beaks ; teeth numerous, vertical, larger distally in two series, about thirty-five anterior and fifty-two posterior, separated by a short vacant gap; inner margins of the valves deeply fluted. Lon. 46, alt. 27, diam. 26 mm. TRANSACTIONS OF WAGNER 648 TERTIARY FAUNA OF FLORIDA This species is easily recognized by its numerous oblique ribs and com- pressed posterior end. Scapharca (Scaphareca) acompsa n. s. PLATE 33, FIGURE 15. Oligocene of the Chipola River, Florida, marl. Shell rectangular, elongate, rather compressed, with low prosoccelous beaks, situated at about the anterior fourth of the whole length; right valve with about thirty-six flattened radial ribs, with much narrower interspaces ; the anterior (twenty-two) ribs are mesially divided by a sharp groove and feebly rippled above; the posterior ribs are flat, smooth, and increase in width backward; the anterior end of the shell is evenly rounded, the base straight and parallel with the hinge-line, the posterior end wider, a little produced below and with a conspicuous angle above; cardinal area long, very narrow, with one or two grooves, and bordered behind with an elevated margin; hinge-line straight, long, with numerous small, uninterrupted teeth very short mesially, longer and somewhat more oblique distally; inner margin of the valves fluted, shell thin and delicate. Lon. 20, alt. 10.5, semi-diam. 4.5 mm. Only two right valves of this little species have been examined. It resembles the young of A. hyfomela but is immediately distinguishable by its more compressed and rectangular form and smooth, flat posterior ribs. Scapharca (Scapharca) triphera n. s. PLATE 33, FiGuRE 6. Pliocene marls of the Caloosahatchie River, Florida; Dall. Shell subequivalve, of moderate size, elongate, not much inflated, sub- rectangular, with low beaks slightly prosoccelous and marked by a conspicuous wide mesial sulcation; umbones situated at the anterior third of the length; left valve with about thirty-eight rounded subequal ribs separated by narrower interspaces; in the adult about a dozen of the anterior ribs may be squared off and deeply mesially sulcate near the margin, while a few of the ribs on the posterior dorsal slope are narrower, smoother, and more widely separated ; transverse sculpture of elevated lines which are somewhat regularly spaced, and in crossing the ribs develop into sharp, thick transverse nodulations ; cardinal area very narrow and with an elevated margin behind, slightly wider in front of the beaks, longitudinally striate; ends of the hinge-line angular; anterior end bluntly rounded, base parallel with the hinge-line, posterior end FREE INSTITUTE OF SCIENCE 649 TERTIARY FAUNA OF FLORIDA subtruncate, a little produced below; hinge with numerous rather crowded subvertical teeth in an uninterrupted series; inner margin of the valves deeply fluted. Lon. of largest valve 28, alt. 14; of younger valve 18, alt. 8.5, diam. 7 mm. The larger valves of this rare species are distorted or worn so that a younger one has been selected for figuring. The most conspicuous feature of the shell is the deep sulcation of the beaks, which gives them a bilobed appearance. Scapharea (Scapharca) donacia n. s. PLATE 33, FIGURE 13. Oligocene marl of Bowden, Jamaica; Bland. Shell small, donaciform, moderately plump, with rather elevated proso- ccelous beaks at about the anterior third; valves almost similarly sculptured ; left valve with about twenty-four low, strap-like, narrow radial ribs with somewhat wider interspaces; the ribs are plain, smooth, and entire on both valves; on the left valve the interspaces are crossed by numerous equidistant elevated lines which do not appear on the ribs; on the right valve the inter- spaces are only marked by lines of growth; hinge-line short, cardinal area very narrow, smooth; anterior end larger, rounded; posterior end produced and attenuated ; hinge-teeth small, similar, slightly divergent ; internal margin of the valves with deep short flutings. Lon. 6.8, alt. 4.5, diam. 3 mm. This little shell has no very marked characters, but appears to be adult, and not very similar to the young of any of the species associated with it. Scapharea (Scapharca) auriculata Lamarck. Arca auriculata Lam., An. s. Vert., vi., p. 43, 1819 ; Reeve, Conch. Icon., Arca, pl. vi., fig. 35, 1844. ? Oligocene of Bowden, Jamaica, Henderson; Pliocene of Limon, Costa Rica, Gabb; Pleistocene of the Antilles, various collectors. Recent, from Key West to Martinique, in fifteen to forty fathoms. The fossil from Bowden seems to be this species, though somewhat worn ; that from Port Limon is certainly the same as the recent shell. Section Avgina Gray. Scapharca (Argina) tolepia n. s. PLATE 33, FicurEs 7, 8. Arca pexata Guppy, Geol. Mag., Oct.; 1874; not of Say, 1822. TRANSACTIONS OF WAGNER ; TERTIARY FAUNA OF FLORIDA Oligocene of Rio Amina, St. Domingo; Bowden, Jamaica, and Cumana, Venezuela. Shell small, thin, greatly inflated, rounded, with incurved prosoccelous beaks; the left valve larger, the sculpture of the two valves slightly discrep- ant; left valve with about thirty-four subequal, rounded, minutely nodulous, radial ribs, separated by narrower channelled interspaces, and crossed by fine incremental lines; right valve with the ribs narrower, flat, and straplike, only a few of the anterior ones showing nodulation; hinge-line short, straight, hardly angular at the ends; the beaks nearly attaining the anterior fourth of the length of the shell; cardinal area very narrow behind the beaks and with elevated margins; in front of the beaks slightly wider, very short; its surface with a few irregular longitudinal grooves; hinge-teeth in two series, the an- terior short and more or less broken up into granules, separated by a very narrow gap from the posterior series, which is about twice as long, with small, numerous vertical teeth, becoming longer and more oblique distally ; internal margins of the valves with short, deep flutings. Lon. 28, alt. 26, diam. 27 mm. This little shell is doubtless an ancestor of Say’s shell, from which it differs by its smaller size, more rotund. shape, finer and more nodulose sculp- ture, and greater inflation. Scapharea (Argina) campechensis Dillwyn. “« Pectunculus dense et profunde striatus, ovali figura,’ Lister, Hist. Conch., tab. 237, fig. 71, 1770; Bay of Campeachy. Arca No. 22; Schroter, Einleit. Conch., iii., p. 288, 1786. Arca campechensis Gmel., Syst. Nat., vi., p. 3312, 1792. Arca ovals Bruguiére, Encyc. Meth., p. 110, 1792. Arca dechivis Solander MSS., fide Dillwyn, 1817. Arca campechensis Dillwyn, Descr. Cat. Rec. Sh., 1, p. 288, 1817 (Syn. partim. exclus.), Jamaica and Carolina; not of Wood, Ind. Test., p. 46, pl. 9, fig. 28, 1825. Arca pexata Say, Journ. Acad. Nat. Sci. Phila., ii., p. 268, 1822. Arca scapha Ravenel, Cat., p. 5, 1834, fide Stimpson. Arca americana (Gray) Wood, Index Test. Suppl., pl. 2, Avca, fig. 1, 1828; zbid., ed. Hanley, p. 205, 1856; Tryon, Am. Mar. Conch., p. 179, pl. 37, fig. 470, 1874. Arca americana Rve., Conch. Icon., Avca, fig. 21, 1844; Holmes, Post-Pl. Fos. S. Car., p. 19, pi. 4, fig. 2, 1858. Arca pexata Greene, Mass. Cat., 1833; Gould, Rep. Inv. Mass., p. 95, fig. 60, 1841 ; Reeve, Conch. Icon., Avca, fig. 22, 1844; De Kay, Nat. Hist. N. Y., Moll., p. 176, pl. 12, fig. 311, 1843; Stimpson, Shells of N. Engl., p. 8, 1851. Arca campechensis Ravenel, Cat. Coll., p. 5, 1834; Arango, Moll. Cubana, p. 262, 1880. FREE INSTITUTE OF SCIENCE 651 TERTIARY FAUNA OF FLORIDA 5 Arca FHolmesi Stimpson, S. I. Checklist, p. 2, 1860; Tryon, Am. Mar. Conch., p. 179, pl. 37, fig. 471, 1874. Not Arca americana Orb., Moll. Cuba, ii., p. 317, pl. 28, figs. 1, 2, 1853. This very-interesting species, of which the synonymy might be much extended, affords an excellent illustration of the effects of environment upon the recent form. Its northern limit is at Cape Cod, where the shell is often large, always coarse, and with a dense hirsute periostracum. Like many of the Scapharcas, it varies in outline from quite round to ovate quadrate; the sculpture of the two valves is discrepant, that of the left valve showing ribs which are narrower, flatter, and less prominent than those of the other valve and often impressed in the middle longitudinally, or even divided by a mesial groove more or less extended from the margin. The ribs of the other side are not grooved, and the literature is so at variance with itself and the facts, in attempts to discriminate the several varieties, that I can only suggest as an explanation that the writers in some cases were unaware of the discrepancy between the valves and compared opposite sides. As we proceed southward, in this species, as in many other shells, we find the shell becoming less earthy and more porcellanous, the sculpture more neat, the periostracum less pro- fuse, and the general size less. South of Cape Hatteras the chalky, thin type, common in the north, is seldom if ever found. In the Gulf of Mexico and the Antilles the shell is still smaller than in the Carolinas, and, with its de- crease in size, the sulcation of the ribs becomes more generally obsolete. A somewhat similar series of differences is observable in the Pleistocene fossils, though less pronounced. Gmelin’s description was inadequate, and only identifiable by his reference to Lister. The species was elucidated by Dillwyn, who noted its resemblance to Cardium (edule), but whose reference to a figure in the Encyclopédie Meth- odique should be expunged from the synonymy. The typical A. campechensts is the rounded southern form which Stimpson afterwards called A. Holmesi, as he himself recognized. Say’s description of. A. pexata included all the varieties of our eastern coast, but Gould first de- scribed the shell so as to make this name apply more particularly to the somewhat elongated, earthy northern variety. Gray’s A. americana was founded on a very elongated, more porcellanous form, such as is common in South Carolina waters. The study of a large series of recent specimens, ranging from Jamaica to Cape Cod, obliges me to recognize that no sharp line of discrimination can be drawn between the several varieties. The number TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA of ribs varies from twenty-six in the roundest, A. HYolmesi, to thirty-five in the most elongated, A. americana ; but the short, round ones often have as many ribs as the elongated specimens. The cardinal area is extremely narrow and depressed, and the portion in front of the beaks is very small. The ante- rior granular series of teeth is much shorter than in A. folepia, and does not extend much in front of the beaks. The species does not descend below the uppermost Miocene, if, indeed, any of the specimens are so old. I have only identified it with certainty from the Pleistocene of Georgia, of Simmons Bluff, South Carolina, of New Jersey, and southern New England. Section Bathyarca Kobelt. Scapharea (Bathyarca) Spenceri n. s. PLATE 32, FIGURES 16, 24. Pliocene of Tehuantepec; Dr. J. W. Spencer. Shell large for the section, inflated, ovate, with prominent prosoccelous beaks; left valve with fine, rounded, concentric elevated lines, close set, and with very narrow interspaces, which show fine, close radial strie, some of which on the anterior end of the shell are more prominent; right valve with fine, close-set radial ribs, coarser on the middle of the shell, separated by narrower, sharp, channelled grooves; transverse sculpture of evenly spaced, low, sharp elevated lines which cross the ribs without becoming much thickened; cardinal area very narrow behind, wider but not distinctly limited in front, the cardinal margin elevated anteriorly, with seven or eight con- centric grooves mostly behind the umbones; ends of the hinge angular behind; the teeth in two series hardly separated, eight to twelve in front, ten to fourteen behind, not crowded, smaller mesially, larger and more oblique distally, the anterior series somewhat irregular; inner margin of the valves with fine crenulations, stronger in the left valve, the outer edge almost or quite entire. Lon. 18, alt. 15, diam. 14 mm. This is the largest species of the section, and was collected by Dr. J. W. Spencer about seventy kilometres west of the eastern terminus of the Tehu- antepec Railway from a cutting, together with a number of other species, all of which indicated that they were deposited in deep water, probably between one hundred and fifty and four hundred fathoms in depth, judging by analo- gous recent species. The matrix isa fine, soft, grayish mud like that of deep- water deposits of the same kind, and its presence with the fossils points to a Post-Pliocene elevation of this part of the land of at least one thousand FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA : feet. For the formation in which it occurs, and which is clearly distinct from any yet described from middle America, Spencer has proposed the name of the Coatzocoalcos formation, from the Coatzocoalcos River, which drains the coastal plain immediately to the eastward. The species is named in honor of Dr. Spencer, who collected it. Scapharea (Bathyarca) Hendersoni n. s. PLATE 33, FIGURE 9. Oligocene of the Bowden beds, Bowden, Jamaica, where it was collected by J. B. Henderson, Jr., and Mr. Charles T. Simpson. Shell very small, much inflated, the hinge-line as long as the shell, which is of a rounded triangular form, with rather prominent prosoccelous beaks; left valve with fine, elevated, rounded concentric lines, crossed by closer, less promi- nent, and finer radial lines; in the right valve, as usual in this section of the genus, the radial sculpture predominates over the concentric, the latter though present being inconspicuous; cardinal area moderately wide, the beaks being nearly medial, the surface of the area longitudinally striated ; hinge with about five nearly vertical anterior teeth separated by a wide unarmed gap from six or seven smaller, more oblique posterior teeth; margin of the valves thin, entire, or microscopically crenulated; the inner edges of the adductor scars slightly raised above the inner surface of the valve. Lon. 2, alt. 2, diam. 2 mm. This minute little species is obviously adult, and about ten valves were obtained. It resembles A. pectunculoides Scacchi and A. glomeriula Dall, of the recent fauna, but is smaller, more inflated, and more triangular than either of them. It is named in honor of Mr. Henderson, during whose explorations in Jamaica it was collected. Another species of the same group with more conspicuous radial sculpture and a marked depression radiating mesially from the beaks was obtained by Professor R. T. Hill from the Oligocene of Monkey Hill, on the line of the Panama Railway, but the two valves obtained are hardly perfect enough for description. Section Anadara Gray. Scapharea (Anadara) rustica Tuomey and Holmes. PLATE 31, FIGURES 6, 9. Arca rustica Tuomey and Holmes, Pleioc. Fos. S. Car., p. 29, pl. 11, figs. 6-10, 1857. Not A. rustica Contejean, 1859. Arca crassicosta Heilprin, Trans. Wagner Inst., i., p. 96, pl. 13, fig. 30, 1887: Dana, Man. Geol., 4th ed., p. goo, fig. 1508, 1895. TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA 654 _ Pliocene of the Waccamaw beds of South Carolina; and of the Caloosa- hatchie, Shell Creek, Alligator Creek, and Myakka River, Florida; Willcox and Dall. The collection of more material since Professor Heilprin’s publication leaves no doubt whatever as to the identity of this splendid species with that of Tuomey and Holmes. It seems to be characteristic of the southern Plio- cene. The beaks are much incurved and distinctly prosoccelous, the cardinal area short and wide in front of them, long and narrow with much elevated margins behind; the anterior part of the area is transversely grooved at right angles to the hinge-line; the posterior part has converging grooves, thus forming three or four concentric triangles. The hinge is composed of a short anterior and long posterior series of subequal vertical teeth vertically striated on their flat surfaces; there are over forty teeth, of which twelve are anterior; the two series are closely approximated. Many of the specimens have a strong posterior auriculation which is more prominent in the young; one specimen measures thirty-two millimetres on the hinge-line and twenty-eight millimetres below the auriculation. An adult measures fifty-three millimetres long, thirty-six millimetres high, and forty millimetres in diameter. The largest valve obtained is seventy-one millimetres long and has fifty-four posterior and seventeen anterior teeth. In this specimen there are nine longitudinal grooves, and the three or four middle ones are extended in front of the beaks, contrary to the rule in younger specimens, giving the grooved area as a whole the form of a long, narrow “stemmed” arrow-head. In this valve the hinge-line is sixty millimetres long and the vertical of the beak is ten millimetres from the anterior end. On the whole, this is one of the finest and most striking species in our whole Tertiary fauna. The specimen figured is comparatively young. Scapharea (Anadara) catasarea n. s. PLATE 32, FIGURE 20. Pliocene marl of Alligator and Shell Creeks, Florida; Willcox. Shell elongate, solid, subrhomboidal, with very anterior, high, prosocce- lous beaks; right valve with twenty-three strong, narrow, rounded ribs, sepa- rated by wider, very deep channelled interspaces; concentric sculpture of incremental lines, which are slightly elevated at regular intervals, and cause over much of the valve the tops of the ribs to appear obscurely nodulous ; the ribs on the anterior end, though simple in the young, are sharply mesially FREE INSTITUTE OF SCIENCE ; 655 TERTIARY FAUNA OF FLORIDA sulcate in the adult, those on the posterior dorsal slope lower and more rude than those on the body of the shell; the hinge-line is straight, the cardinal area differs from that of A. rustica only by having but a single transverse groove anteriorly between the beaks; both valves are similarly sculptured, but no adult left valve was collected; the hinge-line is straight and shorter than the shell; there are about fifteen anterior and four times as many similar vertical posterior teeth, the proximal ends of the series slightly overlapping ; the hinge-line in the specimen figured is forty-six millimetres long, the ver- tical of the beak falls at 8.5 millimetres from the anterior end; inner margins thickened, with short futings. Lon. 55, alt. 36, diam. 45 mm. This fine species appears to be rare, and was found only at Alligator Creek, where two adult right valves, one young pair, and some fragments were obtained. The young has much the outline of A. auriculata, but is not markedly auriculate. It is proportionately shorter than the adult. The species belongs in the same subordinate group as A. rustica, as shown by the minor characters. A single broken vaive, probably of this species, is among the material from Shell Creek. Secapharca (Anadara) subrostrata Conrad. Arca subrostrata Conr., Proc. Acad. Nat. Sci., vol. i., p. 30, 1841; Fos. Med. Tert., p. 58, pl. 30, fig. 7, 1845. Scapharca tenuicardo Conr., Am. Journ. Conch., v., p. 39, pl. 2, fig. 4, 1869. Scapharca subrostrata Conr., Proc. Acad. Nat. Sci. Phila. for 1862, p. 580, 1863. Miocene of Maryland in Talbot and Calvert Counties, at Calvert Cliffs, Skipton, Centreville, Plum Point, and other localities; Conrad, Cope, Burns, and Harris. A single valve, stated to be from the Miocene of North Carolina, is in the National Museum. This species appears to be rather common. The cardinal area is grooved longitudinally with numerous rather irregular concentric grooves. This is not the A. swbrostrata of Sowerby (1847) or of Smith, Quart. Journ. Geol. Soc. Lond., 3, pp. 413, 418, figs. 8, 9. A. callipleura Conrad is probably founded on an unusually short specimen of this species. Scapharea (Anadara) aresta n. s. PLATE 33, FIGURE 2. Chesapeake Miocene of Alum Bluff, Calhoun County, Florida; Dall and Burns. TRANSACTIONS OF WAGNER 656 TERTIARY FAUNA OF FLORIDA Shell of moderate size and thickness, arcuate below, straight above, with small but prominent prosoccelous beaks; left valve with twenty-seven square- topped, narrow, entire radial ribs, separated by wider interspaces; the ribs on the middle of the shell are somewhat narrower than the others; all are crossed by evenly spaced, moderately prominent elevated lines, festooned in the inter- spaces, and forming small, square ripples on the ribs; both valves similarly sculptured ; cardinal area narrow, with elevated margins behind, wider and short in front of the beaks; the portion in front of the beaks is longitudinally striated, behind the beaks there are three or four concentric, lozenge-shaped groovings; a single transverse groove usually passes between the beaks; hinge-line straight; teeth in two nearly equal series, overlapping a little proximally, the teeth rather crowded and nearly vertical; base of the valves arcuate, rounded into the anterior end, posterior end a little produced; in- ternal margins of the valves fluted. Lon. 41, alt. 28, diam. 26 mm. This very neat and distinct species appears to be the most common Ark in the upper or Miocene bed at Alum Bluff. Scaphareca (Anadara) campsa n. s. PLATE 32, FIGURE 21. Chesapeake Miocene or upper bed at Alum Bluff, Florida; Dall and Burns. Shell of moderate size, solid, and heavy, with a straight and angulate upper margin, obliquely rounded anterior, produced posterior, and arcuate basal margin; beaks low, much incurved, mesially impressed, and rather anterior; left valve with about twenty-two narrow ribs separated by wider interspaces, crossed by little elevated, regularly spaced incremental lines; the ribs are not nodulous, the anterior ones are flattish or rarely have a shallow sulcus mesially near the margin; they are subequal, but in specimens in which the mesial depression of the valve is especially strong, the ribs included in it are narrower and closer together than usual; hinge-line nearly as long as the shell, angular, but not auriculate distally; the beaks are within the anterior third; cardinal area wider in front, narrow behind, longitudinally striated with a few grooves which circumscribe a “ stemmed” arrow-head figure, few of them reaching as far forward as the beaks; teeth in two adjacent series, the anterior shorter with a pronounced thickening of the shell below it, over the vertical face of which the teeth extend rather irregularly or are supple- mented by denticular wrinkles; posterior series longer, numerous, vertical, FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA 657 distally much wider, and more or less oblique; interior margin of the valves with strong, short flutings. Lon. 47, alt. 28, diam. 27 mm. This is quite a peculiar species, the teeth of which recall Avgiva, while all the other characters of the shell indicate its section to be Auadara, another instance, if one were needed, to illustrate the mutability of the dental forms in this family. It cannot be confounded with any of our other species. Scapharea (Anadara) clisea n. s. PLATE 33, FIGURE 25. Chesapeake Miocene of Maryland, at St. Mary’s River and Crisfield; of Nomini Cliffs, Virginia, Harris; and of Walton County, Florida, Johnson. Shell large, heavy, inflated, short, with small, high, somewhat prosocce- lous beaks, the two halves of the wide cardinal area inclined to one another in the adult at an angle of about forty-five degrees ; left valve with about thirty strong, flattened subequal radial ribs with narrower interspaces; in the young the ribs are furnished with small transverse nodulations, which gradually become obscure in the adult; the only transverse sculpture is of the ordinary incremental lines; the ribs in the adult are flat topped and rarely show any tendency to mesial sulcation, and when present it appears only on a few of the anterior ribs near the margin; the anterior end is obliquely rounded to the base, the posterior end a little produced basally; the cardinal area is exceptionally wide, with a single impressed line joining the beaks and six or seven concentric lozenges defined by sharp grooves; a deep groove also bounds the area; hinge-line straight with numerous small vertical teeth, becoming much larger distally and tending to break up into granules at both ends of the series in the senile shell. Lon. 51, alt. 53, diam. 53 mm. This shell is apparently related to A. calipleura and A. staminea Conrad, and a larger series of specimens may oblige us to unite all three as varieties of asingle species. At present, however, the differences seem too great to admit of this course. In d. callipleura the ribs are granulated and triply sulcate, while in the present form they are simple. A. c/’sea has no posterior truncation like that figured by Conrad in A. callipleura. A. staminea is more squarely compressed before and behind, with a tendency to incurvation of the ‘posterior basal margin; it is a smaller shell with more posterior beaks, and less roundly inflated. We have a large series of this species from many localities, and these differences characterize them all. The forms are easily differentiated, so far as our present knowledge goes, and therefore are better TRANSACTIONS OF WAGNER 658 TERTIARY FAUNA OF FLORIDA kept apart. In all the pairs of A. staminea in the collection the right valve is distinctly smaller than and fits into the other, while in A. c/zsea the margins meet evenly. It now remains to enumerate the other Tertiary species of Avca not hitherto mentioned, but which have been referred to American beds by various authors. Nomina nuda. A, dipleuwra Conrad, Bull. Nat. Inst., 1842, mentioned by name as from the Miocene of Maryland, appears never to have been described. A. granulifera Conrad appears by name only in the list of species furnished by Conrad for the appendix to Morton’s Synopsis. Unidentifiable. A. cancellata Tuomey, briefly described and unfigured, from the Eocene of North Carolina, in 1854, is not A. cancellata Gmelin, 1792, or Phillips, 1829, and should be expunged from our lists. A. maaillata Conrad was based on an unrecognizable internal cast from the Miocene of Maryland, and, though briefly described in 1830, has never been figured. Eocene. Arca (fossularca?) inornata Meyer, 1886, from Claiborne, Alabama, is very minute and has not been seen by me. A. gigantea Conrad is probably identical with Czcullea onochela Rogers. Noétia pulchra Gabb, from the Eocene of Texas, 1860, is Zrivacria decisa. There is an A. pulchra of Sowerby, dating from 1824. Oligocene. A. oronlensis Gabb, 1875, is abundant in the black shales of Gatun on the Panama Isthmus. The following species described or men- tioned by Gabb from the Oligocene of St. Domingo have not been figured: A. multilineata Gabb, A. patricia Sowerby, A. pennelli Gabb. Arca trinitaria Guppy, 1866, from the Manzanilla beds of Trinidad, appears to be a good species of the subgenus Woéra. Miocene. “Anomalocardia” trigintinaria Conrad, 1862, from the Miocene of South Carolina, seems to be an Avadara from the brief description, but has never been figured. The following nominal species from the Pacific coast have been so wretchedly figured and described that further study is necessary to identify or discriminate them; they are supposed to be from the Miocene: Arca trilineata Conrad, A. canalis and devincta Conrad, all of which by Gabb are united specifically with A. wzcrodonta Conrad, the most common of the Pacific Miocene species; A. congesta Conrad, and A. obispoana Conrad. FREE INSTITUTE OF SCIENCE 659 TERTIARY FAUNA OF FLORIDA Arca limatula Emmons, 1858, Geol. N. Car., is a typographical error for A, limula Conrad. A. “intea Conrad (in App. Kerr’s Geol. N. Car., 1875) is not A. Zintea Conrad, 1852 (Rep. Dead Sea Expedition under Lieut. Lynch). Pliocene and later. A. Deshayesti Hanley is reported by Gabb from the Pliocene of Costa Rica. Nelson has described and figured an A. Larkinc from the Pliocene (?) of Peru. Gabb describes and figures A. swlcicosta from the Pliocene of California (1866), but the name had previously been used by Nyst in 1836 for a Belgian fossil, and Gabb’s species may take the specific name of schizotoma. Arca velata Sowerby (Indopacific) is reported by Gabb from the Pleistocene of St. Domingo, but his shell is probably a distorted specimen of Arca candida or Hlelblingt. The following is a list of the recent species of Arca belonging to the southern coast of the United States; and any of which might be expected to occur in our later Tertiary or Pleistocene beds: Arca occidentalis Phil., A. umbonata Lam.; Barbatia barbata Linné, B. (Calloarca) candida Gmel., B. (C.) nodulosa Mill., B. (Acar) reticulata Gmel., Barbatia (Fossularca) Adamsi (Shuttlew.) Smith; B. (Cucullaria) asperula Dall, B. (Cucullaria) sagrinata Dall, B. (Cucullaria) profundicola Verrill; Noétia ponderosa Say, Noétia bisulcata Lam.; Scapharca secticostata Rve., S. trans- versa Say, S. Deshayesti Hanley, S. auriculata Lam., S. (Cunearca) incongrua Say, S. (Cunearca) Chemnitzit Phil. S. (Argina) campechensis Dillwyn with varieties fexata Say and americana Gray, S. (Lathyarca) pectunculoides Scacchi, S. (Bathyarca) polycyma Dall, S. (Bathyarca) glomerula Dall. Superfamily PTERIACEA. Famity PINNID. The ancient genus Pizna of Linnzus, as represented in our Tertiaries, is divided into two genera: 1. Pinna proper; with the fibrous layer of the valves mesially sulcate longi- tudinally while the inner nacreous layer is bilobed deeply by the same (closed) sulci. The type of the genus is P. rudis L., the red Pinna of the West Indies. P. fabellum Lam. and P. carnea Gmelin belong to it. 2. Atrina Gray; has the valves unsulcate or without the median carina, and the internal nacreous layer is entire. The type is P. zzgva Ch., and it is represented in our recent fauna by P. rigida Dillwyn (P. muricata auct.) and P. serrata Sby. TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA 660 The fossil Pinnas are very difficult to handle, as the fibrous layer is often entirely lost, the fragile shell is almost invariably crushed and fragmentary, while internal casts are defective in the external ornamentation. For this reason the literature says very little in regard to the genus in our Tertiaries, and only one species has been formally described. Genus PINNA (JL.) Lamarck. Pinna quadrata n. s. PLATE 29, FIGURE 7. Shell straight, thin, acute anteriorly with the valves mesially carinate, the dorsal and ventral areas making about the same angle at the carina as the valves do at the hinge-line; byssal gape long, extending well towards the beaks, narrow behind; sculpture of some five longitudinal ribs on the dorsal areas and two or three below the carina, the surface near the ventral edges almost smooth. Lon. of type 56, vert. diam. 26, carinal diam. 25, apical diam. 6.5 mm. A single internal cast was collected by Mr. Willcox at Richard’s quarry, Ocala, Florida, in the Nummulitic or Ocala horizon of the Vicksburgian Oligocene. Specimens nearly twice as large as the above-mentioned were found by L. C. Johnson at Johnson’s lime sink, Levy County, and Arredondo, Alachua County, Florida, in the Vicksburg limestone. They are remarkable for their rapid increase in diameter. Pinna caloosaénsis n. s. PLATE 26, FIGURE 4. Shell long, slender, straight, narrow, thick, with the valves moderately rounded ; carina not conspicuous in the fossils, but the sulcus very long, deep, and sharp, represented on the interior by a large rounded rib; dorsal area sculptured with about three feeble irregularly longitudinal ridges; ventral area with about the same number, but stronger and sharper. Lon. of type 120, max. dorso ventral height 40, min. do. 10, convexity of the valve at the sulcus behind 12 mm. A single broken valve without the fibrous layer and the apical part of another was obtained from the Pliocene marl of the Caloosahatchie. This species is not unlike P. rvdis in form, but is proportionally much thicker and the sulcus is much larger than in the recent shell, which has no such strong, rounded internal rib, : FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA 661 Pinna carnea Gmelin. Pinna haud ignobilis Chemn., Conch. Cab., viii., p. 212, pl. 87, fig. 769, 1785. Pinna pernula Chemn., of. cét., viii., pp. 211, 242, pl. 92, fig. 785, 1785; Arango, Moll. Cuba, p. 264, 1878; Orbigny, Moll. Cuba, ii., p. 325, 1853; not of Reeve. Pinna carnea Gmelin, Syst. Nat., p. 3365, 1792; Solander, Portland Cat., 1796; Des- hayes, in Lam. An. s. Vert., ed. ii., vol. vii., p. 61, 1836. Pinna degenera Link, Beschr. Rostock Samml., p. 159, 1807. Pinna flabellum (Lam.), Reeve, Conch. Icon., Pina., pl. x., fig. 18, 1858. Pinna varicosa Lamarck, An. s. Vert., vi., p. 133, 1819; Orbigny, Moll. Cuba, ii., p. 325, 1853. ? Pinna bullata (Swains.) Reeve, Conch. Icon., Pena, pl. ix., fig. 16, 1858. Post Pliocene of the Florida Keys; recent in the West Indies as far south as Trinidad and north to Cape Hatteras, also in the Red Sea. As Chemnitz was not systematically binomial in nomenclature, his acci- dentally binomial name cannot be accepted, though the earliest. This species seems to be distinct from P. vudis, though it is often spinose or strongly ribbed; further study on this point is desirable. The typical P. rudis is not known from Florida, though said to be abundant on the Bahamas. The P. carnea varies from pale salmon color to a brownish white, and may be smooth, or sparsely muricate; it is always thin, straight, and obliquely trun- cate. P. rudis is the only other true Pizza known from the east American subtropical region; the true P. muricata (L.) Rve. is probably an Oriental species, the saricata of American authors belonging to the genus Aézna. Pinna rudis (Linné) Dillwyn. Pinna rudis ., Syst. Nat., ed. xii., No. 1159, 1766, ex parte, Chemn. Conch. Cab., viii., p. 218, pl. 88, fig. 773, 1785 ; Dillwyn, Cat., p. 322, 1817; Hanley, Shells of Lin., p- 148, 1855; Reeve, Conch. Icon., /vmma, pl. x., fig. 19, 1858; Gabb, Journ. Acad. Nat. Sci. Phila., 2d Ser., viii., p. 378, 1881. Pinna pernula Reeve, Conch. Icon., Pinna, pl. 12, fig. 22, 1858; not of Chemnitz. Pliocene of Costa Rica, Gabb; recent in the West Indies, Bahamas, Bermuda, etc., Reeve, Jones, e¢ al. This species is included on the authority of Gabb; I have seen no Florida specimens unless P. carnea is a degenerate form of it. It is not the P. rudis of authors from the Mediterranean and vicinity; the latter is a form of P. nobilis. Genus ATRINA Gray. The condition of the material is such that only provisional descriptions TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA 662 can be given of several of the following species, though their distinctness appears beyond doubt. Atrina jacksoniana Ms So Lesueur, Walnut Hills Fossils, pl. 5, fig. 5, 1829. In the Jacksonian Eocene of Green’s marl bed, at Jackson, Mississippi, and Garland’s Creek, near Shubuta, Clarke County, Mississippi, Burns; and at Creole Bluff, Grant Parish, Louisiana, Vaughan and L. C. Johnson. Shell thin, fragile, rapidly widening, somewhat compressed along the ventral border; sculpture of near the beaks numerous feeble, more or less wavy, longitudinal elevated lines, which become less distinct ventrally, and are obsolete over the greater portion of the shell, which appears from the numerous fragments to have been nearly smooth posteriorly, or with a few feeble concentric wavelets, most prominent ventrally. A fragment (including the beaks), forty-five millimetres long, has a dorso-ventral maximum diameter of thirty-four, and a transverse diameter of about twenty millimetres. The valves are evenly arched, and become more convex behind. The material is abundant but very fragmentary, yet sufficient to establish the identity of the species at these localities and its distinctness from the others mentioned. Atrina argentea Conrad. Pinna argentea Conr., Proc. Acad. Nat. Sci. Phila., ili., pp. 295-6, 1848; Journ. Acad. Nat. Sci., 2d Ser., 1., p. 126, pl. 13, fig. 31, 1848. Vicksburgian Oligocene of Vicksburg, Mississippi, where it is abundant in the form of impressions in a brownish clay ; Conrad and Worthen. It is quite certain from the appearance of the casts that the surface of the valves originally possessed a certain number of small, feeble, spinose pro- cesses along the principal radial ribs. The specimens examined average about eighty millimetres in length. Atrina (argentea var. ?) chipolana n. s.? Upper Oligocene of the Chipola marl, Calhoun County, and of the Oak Grove sands, Santa Rosa County, Florida; Burns. This form is only represented by fragments. It would appear to attain about the size of A. argentea, but to be somewhat more convex and arcuate. The chief distinction is in the sculpture; the dorsal areas of the valves of both have about five equidistant radial riblets; the ventral areas in avgentea have BREESINSRITULE OFS SCIENCE TERTIARY FAUNA OF FLORIDA a few radial ribs near the middle of the valve, below which the sculpture becomes obsolete; in cizpolana the ventral areas are sculptured with distinct oblique, concentric waves, with about equal interspaces; the upper ends of these waves terminate abruptly where they meet the longitudinal riblets, so that the sculpture of the ventral is strongly contrasted with that of the dorsal areas. This form also appears to increase in width more rapidly than the argentea. On the whole, the two appear specifically distinct, but a complete description must be deferred until better material enables the characters to be fully elucidated. Atrina Harrisii n. s. PLATE 29, FIGURE II. Types collected by G. D. Harris (in honor of whom the species is named) from the Miocene at Jones’s Wharf on the Patuxent River, Maryland ; other specimens were found by him near Plum Point, Maryland, and a frag- ment at Magnolia, Duplin County, North Carolina, by Burns. Shell rather thick (the fibrous layer lost in the specimens), ovately rounded behind, moderately convex; hinge-line straight, ventral margin slightly incurved; the surface of the pearly layer shows the dorsal region with numerous fine longitudinal elevated lines, below which the shell is at first nearly smooth, then the ventral region is sculptured with numerous close-set concentric riblets. Length of portion preserved about 150, max. width 60, diam. 32 mm. This species appears to have been not unlike A. serrata Sowerby, but was a much heavier shell with a blunter anterior end. Atrina rigida Dillwyn. Pinna tenuis striata muricata Lister, Conch., t. 370, f. 310; Sloane, Hist. Jamaica, p. 254. Pinna nobilis Chemn., Conch. Cab., vii., p. 224, ev parte, pl. 88, tig. 775, non Linné. Pinna pectinata Born, Test. Mus. Vind., p. 132, non Linné. Pinna vigida (Solander MSS.) Dillwyn, Cat., p. 327, 1817; Reeve, Conch. Icon., Pena, pl. v., fig. 7, 1858. Pinna seminuda Lam., An. s. Vert., vi., p. 131, 1819; not Reeve, Conch. Icon., Pizza, pl. ii., fig. 2, 1858 (= serrata Sby.). Pinna alta Sby., P. Z. S., 1835, p. 84; Reeve, Conch. Icon., vi., fig. 11. Pinna subviridis Reeve, Conch. Icon., Pinna, xvii., fig. 32, 1858. Pinna ad’ Orbignyi Hanley, P. Z. S., 1858, p. 227; Reeve, of. cz¢., xxvi., fig. 49, 1858. Pinna carolinensis Hanley, P. Z. S., 1858, p. 225; Reeve, of. céz., xxxiv., fig. 66, 1859. TRANSACTIONS OF WAGNER 664 TERTIARY FAUNA OF FLORIDA Pinna ramulosa Reeve, op. cit., xxviii., fig. 52, 1858. Pinna seminuda Holmes, P.-Pl. Fos. 5S. Car., p. 14, pl. iii., fig. 2, 1858. Pinna muricata of American authors, not Linné or Reeve. Post Pliocene of Simmons Bluff, South Carolina, Holmes; of Charlotte Harbor, Florida, Dall; recent from the vicinity of Cape Fear, North Carolina, through the Antillean and Caribbean region, the eastern coast of Central America, and the northern shore of South* America. The variations of the /zxznxzd@ in connection with their station have been insufficiently taken into account, probably because these rough and fragile shells are unattractive to collectors and rarely gathered in any numbers. If the ground on which they live is hard and stony the shells will be short and wide, with coarse, irregular spines and distorted margins. On soft bottom the shells are more elongate and may be spiny or nearly smooth; on fine, clean sand the spinous processes are often beautifully developed and per- fectly preserved. The young have a smaller number of dorsal radii which may or may not be spiny, the ventral area is generally nearly smooth, while the same individuals, when full grown, will have a profusion of small ridges and minor spines upon them in this area. In clear, still water, especially on sandy bottom, the tubulation of the spines seems to become especially marked. Such a specimen formed the type of Reeve’s P. ramulosa. P. alta Sowerby was founded on a finely grown specimen with shorter spines, and the figure of Chemnitz upon which P. rigtda Dillwyn and seminuda Lamarck were founded is derived from an adolescent shell, as is a’ Orézgnyi Hanley. P. subviridis Reeve is an old, worn specimen, and P. carolinensis the normal adult state. The P. muricata of Linné included several types. That upon which the name has finally been fixed is a true /yzuva, and not an Aérina. Atrina serrata Sowerby. Pinna serrata Sby., Tank. Cat. App., p. v., 1825 ; Genera, fig. 1; Reeve, Conch. Icon., Pinna, xxxiv., fig. 65, 1859. Pinna sguamosissima Phil., in Roemer’s Texas, p. 454, 1849; Hanley, P. Z. S., 1858, p. 226; Phil. Zeitsch. Mal., v., p. 164. Pinna seminuda Reeve, Conch. Icon., nna, ii., fig. 2, 1858; not of Lamarck. Pinna muricata Holmes, P.-Pl. Fos. S. Car., p. 15, pl. ili., fig. 3, 1858; not of Linné. Pliocene of Costa Rica, Gabb; Post Pliocene of Simmons Bluff and Abbapoola, South Carolina, Holmes; of Tampa and Little Sarasota Bays, west Florida, Dall; recent from near Cape Hatteras, North Carolina, to the Caribbean Sea (Guadelupe Island.). FREE INSTITUTE OF SCIENCE 665 TERTIARY FAUNA OF FLORIDA The P. serrata was founded upon a very finely spinulose young shell, which is, however, quite recognizable. The P. sguzamosissima was described from adult Texan specimens. It is the Puna seminuda of most American authors, following Reeve, but not of Lamarck. The only other fossil Pizze which I find recorded from the American Tertiaries are P. (Atrina) alamedensis Yates, from the Miocene of Alameda Creek, Alameda County, California, and P. (Atrina) venturensis Yates, from the Pliocene of Casitas Pass, Ventura County, California. These are figured and described in Bull. No. 4, Cala. State Mining Bureau, San Francisco, 1894, p. 56, pl. iv., figures 53 and 54. The two figures do not afford any evident distinction between the two species. A /inna aleutica, described from Alaska by Eichwald (Geogn. Pal. Bemerk, p. 183, pl. xv., fig. 11, 1871), appears to be of Mesozoic age. Aldrich notes the presence of a very large Pinna (senso lato) in Monroe County, Coffeeville, Alabama, in the lower bed of the Wood’s Bluff group, and also at Nanafalia. Vaughan found a species, possibly referable to A. argentea, in the Jacksonian, at Creole Bluff, Louisiana. Famity MELINIDA. . (Pernide, p. 483.) Genus MELINA Retzius. Ostrea (sp.) Linn., Syst. Nat., ed. x., 1758, p. 699; ed. xii., p. 1149. Mya (sp.) Linné, Syst. Nat., ed. x., p. 671 ; ed. xii., p. 1113. Melhna Retzius, Diss., p. 22, 1788. Perna Lam., Prodr. Nouv. Class., p. 82, 1799; Systéme d’un Nouv. Class. des Vers, p. 134, 1801; Roissy, Conch., vi., p. 105, 1805 ; not of Retzius, 1788, p. 20. Lsogonum (sp.) Bolten, Mus. Bolt., p. 168, 1798; ed. ii., p. 117, 1819; (type Ostrea Zsognomon Gmelin.) Tsognomon Link, Beschr. Rostock Samml., p. 155, 1807; Desh. Enc. Meth., Vers., ii., p. 322, 1830; H. and A. Ads., Gen. Rec. Moll., ii., p. 526, 1857. Pedation Solander (MSS., 1786), fide Dillwyn, Cat. Rec. Sh., p. 282, 1817. Sutura Muhlfeldt, Entw., p. 65, 1811; type Ostrea ephippium L. Flippocheta Sangiovanni, fide Phil., Moll. Sicil., ii., p. 55, 1844. Melina Schum., Essai, pp. 39, 111, 1817; Gray, P. Z. S., 1847, p. 200; Phil. Handb. Conch., p. 372, 1853; Meek, Smiths. Checkl. Mioc. Fos., p. 6, 1864; Inv. Upper Miss., p. 24, 1876. Not Peyna, Adanson, 1757, Klein e¢ a/. The ancient Continental custom of a professor writing for a favorite pupil TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA 666 a dissertation for the latter to defend on his examination for a degree, is responsible for the confusion which has led to the ascription of this genus and others contained in the same paper to Philippson, for whom the disserta- tion was written, as well understood by the earlier writers. It is less clear why the acceptance of the genus (which even Linnzus had it in mind to adopt in his proposed thirteenth edition of the Systema Nature) should have been made under a wrong name, and a name already proposed for a different group by Retzius himself. In preparing the list of families (p. 483 axtea) the name Perna was incautiously accepted from Fischer without investigation. The latter, while admitting it to be “ well characterized and prior to Perna Lam.,” objects that Retzius’s first species cited is an Avicula (A. semiaurita L.). It is enough that the name Perna was already in use and not available for Lamarck to use again; but, apart from this, Chemnitz, the chief iconographer of that time, had figured a A/ehna under the name of Ostrea semiaurita Linnzus, whence Retzius doubtless derived it; Linnzeus him- self, in his manuscript notes on Ostrea senuaurita for the proposed thirteenth edition of the Systema, states that its hinge was like that of Ostrea perna, of which Solander thought it only a variety, and authors since have differed as to the generic place of the species. If every genus in which a single species not belonging to it was included by the originator is to be rejected, only monotypical genera will remain. There is no warrant for the assumption that the first species is necessarily the type, and if it is found to differ from the generic diagnosis while others in the list agree with the generic characters given in the diagnosis, that is sufficient to exclude the divergent species from the position of type. As a matter of fact, it appears clearly from Retzius’s paper that no type was selected, though O. perna L. may be inferred, and Ostrea ephippium was recognized and this species fixed as type by Schumacher and all subsequent revisers until the advent of Fischer’s Manual. The synonymy might be much extended, but that given contains the essential citations. Subsequent writers have fixed two sections or subgenera under Melina: 1. /segnomon (Bolten) Link. Shell plain, ventrally produced, with a posterior wing. Type Ostrea tsognomon Gmelin. The name /sogonum appears to have been a misprint, as the word is spelled in several different ways in the Museum Boltenianum. FREE INSTITUTE OF SCIENCE 667 TERTIARY FAUNA OF FLORIDA 2. Mulletia Fischer. Shell ribbed, with a strong posterior wing. Type WZelina Mullett Deshayes. The typical JZehna is mytiliform, compressed, and without auriculation, or, at least, with no differentiated wing; the acute anterior beak in the young becomes obscure in the adult. The genus in America seems to have been confined to temperate waters during the earlier Miocene, though the recent species are subtropical. One fossil JZefna is reported from the Gulf tertiaries in the lowest Eocene. Melina maxillata (Deshayes). Perna maxillata Lam., An. s. Vert., vi., i., p. 142 (syn. excl.), 1819 ; ed. Deshayes, vii., p- 78, 1836. Perna torta Say, Am. Journ. Sci., ii., p. 38, 1820; not of Gmelin (Os¢rea), Syst. Nat., p. 3339; 1792. Perna maxtllata Conrad, Med. Tert., p. 52, pl. xxvii., fig. 1, 1840. Perna Conradi Orbigny, Prodr., ili., p. 127. Tsognomon torta Conr., Cat. Mio. Fos., Proc. Acad. Nat. Sci. for 1862, p. 579, 1863. Melina torta Meek, Smithsonian Checkl. Mio. Fos., p. 6. Perna torta Whitfield, Crust. Moll. Mio. N. J., p. 36, pl. 5, figs. 12-13, 1895. Lower Miocene of New Jersey at Shiloh and Jericho; of Maryland near Easton, Leonardstown, and on the Patuxent; Burns and Palmer. The National Museum has an internal cast which measures twenty-seven centimetres in length, the shell of which could hardly have been less than fifteen inches long. Remarkably perfect specimens of this almost invariably imperfect shell were collected by Mr. W. Palmer at Leonardstown. The identity of the American shell described by Lamarck shortly before Say with the Perna Soldani Desh. of the Italian tertiaries (figured by Knorr, Sowerby [as max/lata| in his Genera, Goldfuss e¢ ad.) has been disputed. They are certainly very similar, but in any case Lamarck says his shell came from Virginia, and the specific name ¢orfa had been previously applied by Gmelin to a variety of I/elna mytiloides Gmelin, so that it was unavailable for use a second time by Say. It seems that Collini in his Voy. Min. (p. 10, pl. 1, fig. 1), printed at Mannheim in 1776, had named the European shell Ostreum polyleptoginglymum ; but, as I have not seen the work, I cannot say whether the binomial system of nomenclature is used in it or not. It is most convenient at present to regard the American as distinct from the European shell. Orbigny, regarding the European form as the true maxd/ata, renamed the American shell P. Conrad. TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA 668 Several species of Perna occur in the literature which do not belong to the genus as‘here understood, but to JZcdiolus. The only other species of Mehna reported from our Tertiary are the unfigured JZ montana Conr. (Pac. R. R. Reps., vii., p. 195, 1857), from San Buenaventura, California, of which nothing seems to have been seen since it was described by Conrad, and the Perna cornelliana Harris, from the Midway stage of Alabama, near Clayton. The remains of this species are quite imperfect, and it is not practicable to make comparisons with JZ. maaillata. Famity PTERIID. Genus PTERIA Scopoli. Pierta Scopoli, Intr. ad Hist. Nat., p. 397, 1777; (sole ex. Mytilus hirundo J..) Avicula Olivi, Zool. Adriat., p. 125, 1792. Margaritifera Humphrey (ex parte), Mus. Calon., p. 44, 1797 (afud Da Costa, 1776, non binom.). Pinctada Bolten, Mus. Boltenianum, p. 167, 1798. vicula Lam., Prodr., p. 82, 1799. Unionum Link, Beschr. Rostock Samml., p. 155, 1807. Margaritiphora Meg. v. Muhlf., Entw., p. 66, 1811. Meleagrina Lam., Extr. d’un Cours, p. 104, 1812; An. s. Vert., vi., 1, p. 150, 1819. Margarita Leach, Zool. Misc., i., p. 107, 1814; Swainson, Zool. Ill., 2d Ser., ii., pl. 55, 1831; not of Leach, 1819, or of Lea, 1838. Perlamater Schum., Essai, p. 107, + Avicila, p. 136, 1817. Anonica Oken, Handb. d. Zool., 1815 ; Naturg. fiir Schulen, p. 652, 1821. The present group was called Margaritifera by J. Woodward in 1728, a name long antedating Klein’s Avicu/a, but not introduced into binomial no- menclature until after the publication of Prerza by Scopoli. The Tertiary and recent forms include the following subgenera: Pterias.s. Type Mytilus larundo Linne. Margaritifera Humphrey. Type WM. margariferus Linné. Electroma Stoliczka. Type Avicula smaragdina Reeve. Of these the latter may be represented in the recent fauna of the Antilles by Avicula Candeana Orb., which seems to owe its characters to commensalism with sponges; MJargaritifera is represented by the Antillean pearl-oyster, MM. radiata Leach, but, curiously enough, neither is known as an American Tertiary fossil. Of typical Prerta there are but few in our Tertiary, and these are often FREE INSTITUTE OF SCIENCE 669 TERTIARY FAUNA OF FLORIDA represented by very imperfect material. In the Eocene of New Jersey, Con- rad has found an unrecognizable internal cast to which he has given the name of P. annosa. It is regarded as a Gastropod fragment. A well-established species is P. mula Conrad (+ claibornensis Lea, and t7goma Conr. non Lam.) from the Claiborne sands. The Oligocene of Vicksburg has furnished the P. argentea Conr., that of St. Domingo and Bowden, Jamaica, the P. mornata of Gabb, the Miocene of Virginia, the P. multangula of H. C. Lea. An unnamed species has been observed in the Midway stage of the Eocene of Georgia by Professor G. D. Harris. De Gregorio has named an unrecog- nizable fragment from Claiborne Avcula cardiacrassa, but there is nothing to indicate any distinctive specific characters in it. Cossmann, after the ex- amination of a full series, unites it to A. clacbornensis. Pteria argentea Conrad. Avicula argentea Conr., Journ. Acad. Nat. Sci., 2d Ser., i., p. 126, pl. 12, fig. 10, 1848 ; Proc. Acad. Nat. Sci. Phila., iii., p. 295, 1847. Lower Oligocene of Vicksburg, Mississippi; Conrad. Pteria (argentea var. ?) chipolana Dall. Upper Oligocene of the Chipola beds on the Chipola River, the lower bed at Alum Bluff, etc., Calhoun County, Florida; Burns and Dall. Small, with a straight hinge-line and narrow, deep ligamentary sulcus, the right valve with a small, well-marked cardinal tooth fitting into a small pit in the opposite valve; anterior wing short, small, with a narrow byssal sinus marked on the auricle by a short groove, external surface smooth, the posterior wing feebly set off; valves rather compressed, none of the valves exceeding twenty-five millimetres in length. It is probable that this represents a species distinct from that of Vicks- burg, but the material in my possession is insufficient to determine the question, but the type of P. argentea shows little trace of a byssal sinus and is more inequilateral than our shell. Pteria multangula H. C. Lea. Avicula multangula H. C. Lea, Trans. Am. Phil. Soc., ix., p. 245, pl. 35, fig. 31, 1845. Miocene of Petersburg, Virginia, Lea; and of the upper bed at Alum Bluff, Florida, Burns. TRANSACTIONS OF WAGNER 670 TERTIARY FAUNA OF FLORIDA This species, from the fragments, should reach a considerable size. Lea’s type was a very small shell. The beaks are less prominent than in P. argevtea, the byssal sinus is obsolete or feeble, the right valve has a marked semilunar pit apparently to receive a tooth from the opposite valve; the surface appears to be more or less lamellose in the adult. Pteria colymbus Bolten. Pinctada colymbus Bolten, Mus. Boltenian., p. 167, 1798 ; Chemn., Conch. Cab., viii., p. 141, pl. 81, fig. 723, 1785 ; Morch, Cat. Yoldi, i1., p. 53, 1851. Avicula atlantica Lam. (ex parte), An. s. Vert., vi., 1, p. 148, 1819. Avicula hirundo Gmelin, Syst. Nat., p. 3357, 1792, er parte, non Bolten. Avicula alico Phil., Zeitschr. f. Mal., vi., p. 20, 1850. Avicula chloris Phil., Zeitschr. f. Mal., viil., p. 54, 1853. Avicula macroptera Beau, Journ. de Conchyl., i1., p. 426, 1851; Krebs, Cat., p. 132, 1864, not of Reeve. Avicula communis Krebs, Cat., p. 131, 1864, not of Lam. Avicula heteroptera Krebs, Cat., p. 131, 1864, not of Reeve. Avicula pteria Krebs, Cat., p. 131, 1864, not of Scopoh. Avicula atlantica Holmes, P.-Pl. Fos. S. Car., p. 14, pl. 3, fig. 1, 1858. Avicula hirundo Say e¢ a/., non Bolten. Pliocene of the Caloosahatchie beds, south Florida, Dall; Post Pliocene of Abbapoola and John’s Island, South Carolina, Holmes; recent on the southeastern coast of the United States and in the West Indies in shallow water. Pteria hirundo Bolten. Mytilus hirundo Linné, Syst. Nat., xii., p. 1159, 1766, ex parte. Pinctada hirundo Bolten, Mus. Boltenian., p. 167, 1798; Chemn., Conch. Cab., viil., p. 142, pl. 81, fig. 725. Avicula tarentina Lam., An. s. Vert., vi., 1, p. 148, 1819. Mediterranean. Pteria hirundo var. vitrea Reeve. 2? Avicula strix Phil., Zeitschr. f. Mal., vi., p. 22, 1850; (on Sargasso.) Avicula vitrea Reeve, Conch. Icon., Avicu/a, pl. 18, fig. 68, 1857 ; (West Indies.) Avicula hirundo var. nitida Verrill, List Fish Com. Moll., p. 281, 1884. Post Pliocene of the West Indies and Costa Rica; recent, on the south- eastern coast of the United States and in the West Indies in rather deep water. FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA 671 Superfamily OSTRACEA. Famity OSTREID-. Genus OSTREA (L.) Lamarck. Type Ostrea edulis Linne. The genus Ostvea, as restricted by Lamarck and represented in our Tertiaries, comprises several conchological groups. The typical Ostrea, which is moncecious, producing large embryos which are incubated for a considerable period in the parental gill-lamine, is not known to occur in America. Our common oysters belong to a group characterized by being dicecious and discharging the seminal products directly into the water, which must take the name of Crassostrea Sacco.* This is typified by Ostrea wir- ginica Gmel. and represented in the present European fauna by Ostrea angu- fata Lam., known there as the Portuguese oyster. It being impracticable to determine the affinities of the fossil oysters with relation to these two sub- genera, they will be considered here under the common generic name. It is not improbable that all the American oysters belong to the subgenus Crass- ostrea. Conchologically, the ostrean element of the American invertebrate fauna presents three types which exist in the present fauna and may be traced throughout the Tertiary, their outlines becoming less sharp as we recede in time. In the Eocene a fourth group may be added which seems to have left no descendants. Subgenus Crassostrea (Sacco, emend.) Dall (+- Gigantostrea Sacco, 1897). Valves discrepant, the upper valve smoother, the lower valve coarsely and irregularly plicate, with the distal margins little if at all crenulated, the hinge- margin not alate, the apices straight or oblique but not spirally twisted. Type O. virginica Gmel. Eocene to recent. Section Cymbulostrea Sacco, 1897 (Cubitostrea Sacco, 1897). Shell with the plications of the lower valve regular and fine, species usually of small size. Type O. cyimbula Lamarck. Eocene. It is a curious commentary on the distance from nature attained by a certain school of systematists, that their classifications enable them to put * This name has been published since the present revision was completed, and is therefore sub- stituted for the MS. name I had used. It is to be regretted that the diagnosis offered by the author of Crassostrea has no systematic value and is even opposed to the facts. TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA two oysters bred of the same parent in different subgenera, according to their growth in quiet water on a pebble, or in running water on a twig. Subgenus Lopha Bolten, 1798 (Rastelum [| Llhwyd, 1699] Fischer, 1886; Alectryonia Fischer de Waldheim, 1807; Dendostrea Swainson, 1840). Valves similarly sculptured, sharply radially plicated, with their margins similarly crenulated, without alz; their apices not spiral, the shell frequently arcuate. Type Ostrea crista-galli Linné. Eocene to recent. Subgenus Ostreola Monterosato, 1884. Valves with small, close radial riblets, less conspicuous on the upper valve, but ending on the margins with small crenule, otherwise as in Crassostrea. Type Ostrea stentina Pay- reaudeau; ex. O. eguestris Say. Eocene to recent. Subgenus Grypheostrea Conrad, 1865. Valves discrepant, the lower valve smooth or concentrically striate, larger, with incurved apex; hinge-line with a posterior and sometimes an anterior wing; upper valve with distant elevated concentric lamine, flattish or concave, with short apex; the margins of the valves entire. Type Ostrea subeversa Conrad = O. eversa (Mellv. ?) Conrad, + ? O. vomer Morton. Eocene. As we recede in time the lines of demarcation between these groups gradually fade, and yet, even in the Cretaceous, species are found which illustrate them. The oldest type is that of Crassostrea. The group called Gryphea is connected by slow gradations with Ostrea, but of the species which best illustrate Gryphea none is known from Tertiary or recent faunas. Exogyra is a clearly distinct genus when confined to species with the typical characters. The subgenus Grypheostrea Conrad was founded on an Eocene shell closely resembling a French Eocene species (cf. Smithsonian Checklist Inv. Fos.; Eocene, by T. A. Conrad, p. 33, 1866) and hardly distinct from the Cretaceous Ostvea vomer Morton. Subgenus GRYPHAZA Lamarck. Gryphea Lam., Syst., An. s. Vert., p. 398, 1801, ex parte. Gryphea Bosc, Hist. Nat. Coq., ii., p. 307, pl. 15, fig. 1, 1802; Roissy, Hist. Nat. Moll., vi., p. 202, 1805 ; Cuvier, Regne An., ii., p. 459; Woodward, Man., p. 255, 1851. Gryphea (sp.) Lam., Hist. An. s. Vert., vi., p. 197, 1819; Fischer, Man. de Conchyl., p. 927, 1886. Gryphea A. Blainville, Man. de Mal., p. 522, 1825. Pycnodonta F. de Waldh., Bull. Mosc., vili., 1835. (G. vestculavis Lam.) Type Gryphea arcuata Lam., Enc. Meth., pl. 189, figs. 1, 2; not Gryphea Sacco, Moll. Terz. Piem., xxiii., p. 21, 1897. FREE INSTITUTE OF SCIENCE 673 TERTIARY FAUNA OF FLORIDA Although there are no true Gryphzas in our Tertiary, the general con- fusion in the literature in regard to the type of this group, and its bearing on the nomenclature of the genus Ostrea seem to make it desirable to clear up the synonymy. Gryphea was described as a genus by Lamarck in 1801, no type being selected, but a number of species cited, part of which had been figured in other works, to which figures Lamarck applied names; others were unde- scribed, and these names were, of course, zomzna nuda until such time as they might be habilitated. The figures to which Lamarck gave names were to be found in the Encyclopédie Methodique of Bruguiére, pl. 189; Bourget, Mem. hist. nat. petr., pl. 14, 15; and Knorr, Naturg. Verst., ii., part 1, pl. 20, 60, and 62. The first two columns of the following table show the original nomenclature of Lamarck and the figures upon which it was based. The names opposite the first in the third column show the equivalent names, and the fourth column references for the same fossils, used by Lamarck in 1819 when the manuscript species of the first list were first described. Only one reference is given in the second column for each of the first list of names, and preference has been given to the plate of the Encyclopédie, which has by far the most recognizable figures. Lamarck, 18or. | Authority. Lamarck, 1819, | No. Page. G. angulata Lam. -.. . 210 MS. | GraeilataNcarm'y. yy eye I, 198 G. suborbiculata Lam... . .|| Enc., f 34. | Go COWTM@ MAND. <5 3 9 6 2 ol] 2) LOB Gr. enn \Lawin, “55 5 6 © 6 |lIino, jolly Bo), ti 7 Go COMTI NBWING 0 56 6 Go 8 3, UGS G, GiACHIGHE WAM, 6 6 5 0 4 Tine, fs i, Bo lll Gs @rremene Lamm, o oo 6 0 c | 4, 198 G. ajfricama Lam. ..... .| Enc., f. 5, 6. || G. secumda Lam. ..... .- 5, 199 Go Gurniaiia WAIN, 56 5 5 5 3 136 IS, 1 SO), COs || Ge pay WANN, > 5 o 5-0 a 8, 199 (G. Uaissiia@ VAG, 6 6 6 8 3 6 HS}, til, 3h SV Bia) G. dersoa@ WAvINs 5 oo 5 8 7, 199 Garidepnessad aikan acl acne Ms. | G siege Wem, oo 5 5 5 0 12, 200 G. angustata Lam. .... . Ms. Go tgnsda WEIN, 0 5 5 6 2 5 || lO, BOO As Lamarck selected no type, the type must be sought from the first reviser. This was Bosc, in the following year, who cites the described species and figures as an example the G. arcuata, which he refers to the Axomia gryphus of Linné. The next author to treat the group was Roissy, who cites as examples G. suborbiculata and G. arcuata, and figures the latter to illustrate the genus. TRANSACTIONS OF WAGNER 674 TERTIARY FAUNA OF FLORIDA He mentions that the G. angulata was still (1805) undescribed, and that it was not even known in what collection it then was. Cuvier follows in 1817, and gives a diagnosis of the genus and refers for illustration to plate 189 of the Encyclopédie, figures 1 and 2 of which were originally named by La- marck G. arcuata. It is certain that an undescribed species cannot be accepted as a type, and the type must be selected from the described species of the original list accord- ing to the rules of nomenclature. It would seem from the above notes that this type must be the G. arcuata or, if they are identical, the G. gryphus (L.), from which the genus derived its name. In 1819 Lamarck describes the genus again and gives a longer list of species, in which for the first time G. azgulata is described. In this list, as the third column of the above table shows, nearly every one of the species of the original list had its name changed, for what reason is unknown; while the reference to Encyclopédie, plate 189, figures 1 and 2, is transferred from G. arcuata to G. cymbium, perhaps by a copyist’s error. To G. arcuata is added as a synonym G. zucurva Sowerby, from the Min. Conch., ii., p. 21, pl. IA, IONeRS My, ACSSIUCS In his remarks Lamarck states that the group has long been known under the name of Gryphites, which is the name Linné applied to his Azomza eryphus in the Museum Tessinianum, 1753. In 1825, in the first section of his Gryphea, Blainville cites as examples Lamarck’s G. cymbium (Enc. Meth., pl. 189, figs. 1, 2) and G. arcuata Lam., which he figures to illustrate the genus. Woodward in 1851 cites G. meurva Sby. In spite of all this, we find in Gray, Fischer, Tryon, Stoliczska, and Sacco the assumption that G. anxgulata is Lamarck’s type, an opinion entirely with- out proper foundation. Hanley and Salter, from an examination of Linné’s type, refer it to the G. obliquata Sby. The relations of this to the G. avcuata I am unable to determine, and therefore retain the specific name of Lamarck. It is perhaps fortunate that G. angulata is not the type of Gryphea, as anatomical and embryological investigation has shown that this species is simply an oyster of the same type as O. wrginica, and has only a slightly twisted beak to connect it with the fossils properly called Gryphea. This fact was recognized by Sowerby as soon as he became acquainted with the species, and is now beyond question. The characters of this group can hardly be held to be generic, unless by FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA those who are disposed to make a genus of every well-defined species. In allowing it even a subgeneric place I feel that I am giving it more than its just rank, in view of its very feeble distinctive characters. Origin of the Mutations of Ostrea. The oysters are a proverbially difficult group, owing partly to their adherent situs and partly to the fact that they have not hitherto been studied with regard to the direct influence of the environment on individual specimens. That this is very great I have convinced myself from a prolonged study of a multitude of specimens of O. virginica of which the provenance was known, and of many hundred specimens of our Tertiary species, which usually show from the character of the scar of attachment something of the circumstances in which they grew. The conclusions to which I have been led by this study may be regarded as in part provisional, but in the main highly probable, and as furnishing a first contribution to the sort of study which is essential if we would understand the processes of nature through which these animals acquire their most conspicuous external characters. They may be regarded as especially applicable to the Crassostrea group. . Leaving out of account the nepionic characters, the characteristics of the adult shell may be summarized and derived as follows: The most permanent characters of the shell, and the best, if not infallible, guide to specific recog- nition among the puzzling mutations a large series presents, are the form of the hinge-margin, the minute sculpture of the superficial layer of the shell (often denuded in otherwise perfect fossils), and the sculpture of the valve- margins near the hinge and on each side of it. While not invariable in all specimens, these characters, taken together, will usually enable one to refer the individual to its proper place. The characteristics due to situs may be partially summarized as follows: When a specimen grows in still water it tends to assume a more rounded or broader form, like a solitary tree compared with its relatives in a crowded grove. When it grows in a tideway or strong current the valves become narrow and elongated, usually also quite straight. Specimens which have been removed from one situs to the other will immediately alter their mode of growth, so that these facts may be taken as established. When specimens are crowded together on a reef, the elongated form is necessitated by the struggle for existence, but, instead of the shells being straight, they will be irregular, and more or less compressed laterally. When the reef is dry at 8 ; TRANSACTIONS OF WAGNER 676 TERTIARY FAUNA OF FLORIDA low stages of the tide, the lower shell tends to become deeper, probably from the need of retaining more water during the dry period. Such oysters are the so-called “raccoon oysters,’ a name which they get from the visits of that animal at low water to feed upon them. The so-called ‘“‘ raccoon oysters” figured in Dr. C. A. White’s’ Review of the Ostveide@ (Ann. Rep. U. S. Geol. Survey, 1883, pl. 81-2) are not the reef oysters which first acquired this name, but deep-water specimens which had grown in a place where they were subjected to current action. When an oyster grows in clean water on a pebble or shell, which raises it slightly above the bottom level, the lower valve is usually deep and more or less sharply radially ribbed, acquiring thus a strength which is not needed when the attachment is to a perfectly flat surface which acts as a shield on that side of the shell. Perhaps for the same reason oysters which lie on a muddy bottom with only part of the valves above the surface of the ooze are less commonly ribbed. When the oyster grows to a twig, vertical mangrove root, or stem of a Gorgonian, it manifests a tendency to spread laterally near the hinge, to turn in such a way as to bring the distal margin of the valves uppermost, and the attached valve is usually rather deep, the cavity often extending under and beyond the hinge- margin; while the same species on a flattish surface will spread out in oval form with little depth and no cavity under the hinge. ‘ The average life of the ordinary O. virginica when “planted” for sale is about four or five years. In prehistoric times when the reefs were un- disturbed the favored individual might attain a much greater age; in which case the lower valve especially took on excessive thickness, and the cavity of the shell often became considerably elongated and somewhat hourglass- shaped, as in O. contracta Conr., whose characters in typical specimens are distinctly senile, while younger specimens of the same species have the normal form. In the hinge of the oyster the resilium occupies the central ridge, while the ligament covers the edge of the depressions on each side of that ridge. The form and relative position of the muscular scar of the adductor is within certain limits a useful character, but its depression below the general interior surface of the valve or its occasional elevation above it, as in Plicatula, is of no systematic value, being merely a corollary of the rate of growth from the various secreting surfaces. The habit of rapid growth, causing a vesicular character of the shell substance, is more pronounced in some species than in others, and in some specimens of a species than in others; it is rarely the FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA one case that this habit (as in O. percrassa Conr.) has attained a constancy entitling it to systematic significance. Having thus pointed out some of the features which are liable to mislead the student in estimating specific values, we may proceed to consider the species of our Tertiary. Ostrea crenulimarginata Gabb. O. crenulimarginata Gabb, Journ, Acad. Nat. Sci. Phila., 2d Ser., iv., p. 398, pl. 68, figs. 40, 41, 1860. ? O, denticulifera Conr., Journ. Acad. Nat. Sci. Phila., 2d Ser., iii., p. 330, pl. 34, fig. 18, 1858. O. precompressirostya Harris, Rep. Ark. Geol. Surv., il., p. 39, 1894. O. tumidula Aldr., Rep. Geol. Surv. Ala., p. 242, pl. 14, figs. 1, 2, pl. 15, figs. 1, 2, 1894. Midway stage of the southern Eocene, from the well at Little Rock, Arkansas; Prairie Creek, Wilcox County, Alabama; and the Chattahoochie River, near the mouth of Pataula Creek, Alabama. Conrad’s species is described from a specimen too young to show its specific characters; otherwise it is probably identical with that of Gabb. Ostrea pulaskensis Harris. O. pulaskensts Harris, Rep. Ark. Geol. Surv., ii., p. 40, pl. 1, fig. 3, 1894. Midway horizon, at various points in Arkansas. This species is represented in the collection by rather poorly preserved and young material which leaves a suspicion that it is extremely closely allied to O. Hurse Gabb, though not sufficient to show their identity. The valves recall the lower valve of O. subeversa, but have no auriculation. Ostrea selleeformis Conrad. ‘ . selleformis Conr., Fos. Tert. Form., p. 27, pl. 13, fig. 2, 1832 (upper valve). . radians Conr., loc. cit., fig. 1 (lower valve). . aivaricata Lea, Contr. Geol., p. 91, pl. 3, fig. 70, 1833. CROSS) . semtlunata Lea, op. cit., p. 90, pl. 3, fig. 69, fide Conrad. O. falciformis Conr., Am. Journ. Conch., i., p. 140, pl. xi., fig. 1, 1865 ; Proc. Acad. Nat. Sci. Phila. for 1863, p. 291. O. lingua-felis Whitfield, Lam. Rar. Clays, p. 223, pl. 29, fig. 1, 1885. O. glauconoides Whitf., loc. cit., fig. 2. O. stelleformis Conr., Am. Journ. Conch., i., p. 15. 1865 (err. typogr.). Eocene of Claiborne, Alabama; Coffeeville, Alabama; Coggins Point and City Point, James River, Virginia. TRANSACTIONS OF WAGNER 678 TERTIARY FAUNA OF FLORIDA Variety divaricata Lea, Choctaw Bluff, Alabama; Natchitoches Parish, Louisiana; City Point, James River, Virginia. Variety perplicata Dall. Eocene, Caton’s Bluff, Conecuh River, Alabama; L. C. Johnson. Shell very heavy, arcuate triangular, with coarse, rounded, numerous divaricating ribs (twenty-five to forty), no auriculation or posterior sinuosity of the margin near the hinge, the upper valve extraordinarily ponderous, the general form regular and uniform, the valve margins nearly or quite simple. Variety ragifera Dall. Middle Oligocene of the Chipola beds at Alum Bluff and on the Chipola River, Florida, and in the silex beds at Ballast Point, Tampa Bay, Florida; Dall and Burns. Shell rather thin, irregular, coarsely ribbed, more or less imbricated, margin plicate, form tending to ovate or rounded. The above varieties belong to the section Cymbulostrea of Sacco. Variety pauctplicata Dall. Upper Oligocene of the Oak Grove Sands, Santa Rosa County, Florida ; Burns. Shell fan-shaped with acute beaks, thin, with few (seven to fifteen) rather large, loosely imbricated radial but not divaricating ribs, the scales more or less fluted, thin, and elevated; upper valve falcate, with concentric lamine ; structure flattish and thin. This seems remarkably distinct from the others and points towards such species as s#bfalcata Conrad; but the whole series seems to be a continuous development from the Lower Eocene divaricata to the present form. The typical sed/eformis appears to be a merely local development, probably from Some peculiarity of situs of the individuals concerned. It was some time before I could bring myself to unite some of the very distinct looking forms which have been called divaricata with the sed/eformis type, but careful study of a large series has convinced me that this is the proper course. It would seem as if there must be some especial reason for the singularly massive and regu- lar character of the variety perplicata, but occasional specimens of dvaricata, verging on typical se//eformis, exhibit a similar thickening. Gregorio adds a variety vermilla and another variety /e¢a for modifications of sculpture. Ostrea alabamiensis Lea. O. alabamiensis Lea, Contr. Geol., p. 91, pl. 3, fig. 71, 1833. O. linguacanis Lea, op. cit., p: 92, pl. 3, fig. 72, 1833. FREE INSTITUTE OF SCIENCE A Ane Se 679 TERTIARY FAUNA OF FLORIDA O. pincerna Lea, of. cit., p. 92, pl. 3, fig. 73, 1833. (Misprinted pzncera, princerna, and pincema in various works.) O. cretacea Morton (ex parte), Syn. Org. Rem., p. 52, pl. 19, fig. 3, 1834. O. clatbornensis (Conr. MS.), Harris, Bull. Pal., i., pp. 3, 11, 1895. ? O. semtlunata Lea, Contr. Geol., p. go, pl. 3, fig. 69, 1833. Eocene of Claiborne and Gosport, Alabama; Oligocene of Vicksburg, Mississippi, and perhaps of Florida and California. The reason why the name semilunata was not originally adopted for the synonymous oysters of Lea was partly on account of a suspicion that the type of semulunata was a worn, immature specimen of se//eformzs, and partly because the name is less appropriate. There is no reason why the original decision should be changed at present. The O. alabamiensis, when its outer layer is preserved, shows, as noted by Cossmann, fine radial grooving, which is usually lost with the thin dehis- cent coating referred to. The species which is here termed O. mawriciensis would form a direct continuation of the line of the a/abamiensis, and it is not impossible that they should be specifically united, but I have never been able to obtain an absolutely complete specimen of Gabb’s shell, so as to see if the prismatic layer agreed. From mawriciensis to virginica the gap is hardly noticeable. The Californian oyster which has been called O. Zayloriana Gabb is suspiciously close to the present series. Ostrea compressirostra Say. O. compresstrostra Say, Journ. Acad. Nat. Sci. Phila., iv., p. 132, pl. viil., fig. 2, 1824. Gryphaea mutabilis Morton, Journ. Acad. Nat. Sci. Phila., vi., p. 81, pl. iv., fig. 3, 1828; Synops. Org. Rem., p. 53, pl. iv., fig. 3, 1834. O. sinuosa Rogers, Trans. Am. Phil. Soc., N. S., v., p. 340, 1831, and vi., pl. xxvii., fig. I, 1839. O. disparilis Conr., Medial Tert., p. 51, pl. 26, 1840. O. Tuomeyi Conr., Proc. Acad. Nat. Sci., ix., p. 184, 1865 (not of Coquand, 1869, Mon. Ostr., p. 68). 2? O. pandiformis Aldr., Journ. Cin. Soc. Nat. Hist., p. 79, 1887, as of Gabb, Proc. Acad. Nat. Sci. Phila. for 1861, p. 328, 1862. O. Raveneliana Tuomey and Holmes, Pleioc. Fos. S. C., p. 21, pl. 6, fig. 1, 1855 ; Conr., Proc. Acad. Nat. Sci. Phila. for 1863, p. 582. O. bellovacina Conr., Bull. Nat. Inst., ii., p. 172, 1842, not of Lamarck. Eocene: of Piscataway Creek, Upper Marlboro, and Leland, Prince George County, Maryland; lower bed Aquia Creek, of Evergreen, Gloster City, City Point, and Coggins Point, Virginia; also on the Eastern Shore of TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA 680 Virginia, Fort Washington, Virginia, in the North Carolina Eocene, and that of Bell’s Landing, Alabama; a variety alepidota, without raised lamelle externally but with radial grooves, is noted from Aquia Creek and the South Carolina Eocene. Oligocene: of the lower bed at Alum Bluff, Florida. Miocene: of the upper bed at Alum Bluff, Florida; of Grove, St. Thomas, Cooper River, and Darlington, South Carolina; Snow Hill and Duplin County, North Carolina; Grove Wharf, James River, and the Nansemond River, near Suffolk, Virginia, and Imlaytown, New Jersey. Pliocene: of Peace Creek, near Arcadia, Florida ? This well-known shell, though not exceptionally variable, has had many names. A specimen of Gryphea mutabilis Mort., given by Dr. Morton to Dr. Lea and agreeing precisely with Morton’s figure and description, is simply a somewhat worn, smoothish specimen of this species. There is little or no uncertainty about the other synonymes. It is first distinctly noted in the upper bed at Bell’s Landing, Alabama, in the Chickasawan series, whence it occurs through the Eocene, Oligocene, Lower and Upper Miocene, and even, if one or two rather poor specimens can be referred to it, in the Pliocene sands of south Florida. These last may be Miocene redeposited. The specimens from Virginia which grew under advantageous circumstances are often widely alate with much elevated, elegantly fluted concentric lamella. The average specimen, however, has much less prominent alz and imbrications. Comparatively smooth specimens are very close to O. ¢rigonatis. Ostrea thirsze Gabb. Gryphea thirse Gabb, Proc. Acad. Nat. Sci. Phila. for 1861, p. 329. Ostrea thirse Heilprin, Ann. Rep. U.S. Geol. Surv. for 1883, p. 311, pl. 63, figs. 4, 5, 6, 1884. Eocene of the lower Chickasawan series at Nanafalia Bluff, Tombigbee River, and at Eufaula, Alabama. This appears to be a well-marked species, smooth with hardly any tendency to plication, almost nautiloid in form, and belonging to the same group as the next species. Ostrea Johnsoni Aldrich. O. Johnsont Aldr., Geol. Surv. Ala., Bull, p. 41, pl. 6, fig. 6, 1886. Lower Claibornian Eocene of the Monroe County, Alabama, calcareous FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA 681 sand bed; Claiborne, Lisbon, and Newton, Alabama, and at Caton’s Bluff, Conecuh River, Alabama. This is an excellent species with a few strong plications, making the valves claw-like; otherwise close to O. ¢hirse. Ostrea (Gryphzostrea) subeversa Conrad. : Grypheostrea subeversa Conr., Am. Journ. Conch., 1, p. 15, 1865; Checkl. Inv. Fos. Eocene, p. 33, 1866. Gryphostrea eversa (Deshayes) Conr., Checkl. Inv. Fos. Eocene, p. 3, 1866. Ostrea eversa (Mellv.) Heilprin, Ann. Rep. U. S. Geol. Surv. for 1883, p. 310, pl. 64, figs. 5-8, 1884. ? Gryphea vomer Morton, Synops. Org. Rem., p. 54, pl. ix., fig. 5, 1834; zo¢ in Journ. Acad. Nat. Sci. Phila., vi., pl. v., figs 1-3, 1828. Cf. Ostrea lateralis Nilsson, Petr. Suec., p. 29, pl. 7, figs. 7, 10, 1827, and Gryphea can- aliculata Sby., Min, Conch., pl. 26, fig. 1, 1812 (as Chama). ? Cretaceous of the lower Greensand and upward in New Jersey, espe- cially near New Egypt.: Eocene of Upper Marlboro’, Maryland, Conrad; Jacksonian Eocene of Fail Post-Office, and the Zeuglodon bed at Cocoa Post-Office, Choctaw County, Alabama. This species is worth more thorough study by some one familiar with the Cretaceous forms of both Europe and America. Its relations are merely indicated by the above synonymy. Ostrea trigonalis Conrad. Ostrea trigonalis Conr., Proc. Acad. Nat. Sci. Phila., vil, p. 259, 1855; Wailes, Geol. Miss., p. 289, pl. xiv., fig. 10 (bad), 1854; Lesueur, Walnut Hills Fos., pl. 4, fig. 17), De By ine, Hy USAC), ? O. Attwoodit, Gabb, Pal. Cal., ii., pp. 33, 106, pl. ro, fig. 58, pl. 11, fig. 58 4, 1869. ? O. subjecta Conr., Pac. R. R. Rep., vii., pt. 1, p. 193, pl. 2, fig. 3, 1857. (Young shell.) Upper (Jacksonian) Eocene of Jackson, Mississippi; Fail Post-Office and Cocoa Post-Office, Choctaw County, Alabama; Turks Cave, Alabama; Hinds County, Mississippi; Creole Bluff, Grant Parish, Louisiana. Lower Oligocene (Vicksburgian) of Vicksburg, Mississippi; Upper Oli- gocene of White Beach, Little Sarasota Bay, Florida, and Oak Grove, Santa Rosa County, Florida. Miocene of Greensboro’, Choptank River, Maryland; Edgecombe County, North Carolina. TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA 682 Pliocene of Peace Creek, near Arcadia, and Alligator Creek, Florida. The original figure of Conrad is very poor. The species is widespread and recognized by its flat upper valve, few-ribbed lower valve, straight hinge- line, flat hinge-area, with excavated central channel and the peculiar vermicular sculpture of the submargin on each side near the hinge-line. It is not im- probable that O. percrassa Conrad is a peculiar local race of this species and that O. Mortoni Gabb and O. vicksburgensis Conrad are young pebble-grown shells of the same species as the large, well-grown specimens which I regard as normal ¢rigonalis. The differences are, however, so marked that it is probably best to keep them separate for the present, until more is known. O. subtrigonalis of Evans and Shumard is a Cretaceous species. Varieties of O. compressirostra approach very closely to this species. Ostrea vicksburgensis Conrad. O. vicksburgensis Conrad, Proc. Acad. Nat. Sci. Phila., iii., p. 296, 1848; Journ. Acad, Nat. Sci., 2d Ser., i., p. 126. pl. 13, figs. 5, 37, 1848. - O. panda Morton, Syn. Org. Rem., p. 51 (ex farte), pl. 19, fig. 10, 1834. O. Mortoni Gabb, Proc. Acad. Nat. Sci. Phila., p. 329, 1861. Jacksonian Eocene of Fail Post-Office and Cocoa Post-Office, Choctaw County, Alabama; Eocene of South Carolina and Clarksville, Alabama ; Vicksburgian Oligocene of Vicksburg, Mississippi; Burns and Johnson. As previously noted, this species is probably an offshoot of O. “#zgonalvs. The Vicksburg type differs from the Jacksonian only in having the ribs less imbricated and more rounded, a distinction which is not constant. Ostrea falco Dall. PLATE 30, FIGURES 4, II. O. falco Dall, Proc. U. S. Nat. Mus., xvili., p. 22, 1895. Jacksonian Eocene of Cocoa Post-Office, Choctaw County, Alabama, in the Zeuglodon bed; Burns and Schuchert. This remarkably distinct species is well characterized by its cellular lower valve, radiately striate, flat, arcuate, and hooked upper valve, and the strong denticulations of the submargin. Held horizontally, the profile of the upper valve is remarkably like that of the head of a raptorial bird, and this form is exceptionally constant. Ostrea podagrina Dall. PLATE 30, Ficures 5, 0. O. podagrina Dall, Proc. U. S. Nat. Mus., xviii., p. 22, 1895. FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA Upper Eocene of the west bank of the Suwanee River, near the Sulphur Spring, Florida; Eldridge. This singular species differs from O. percrassa and heavy specimens of O. trigonalis in its few strong plications and the rounded lateral portions of the hinge-area, which in the above-mentioned species are conspicuously flat. Ostrea pererassa Conrad. O. percrassa Conr., Fos. Med. Tert., p. 50, pl. 25, fig. 1, 1840; Proc. Acad. Nat. Sci. Phila., xiv., p. 582. ? Eocene of Wood’s Bluff, Alabama, and near Lawrence, Mississippi; L. C. Johnson (var. sy/verupis Harr.). Miocene of Stow Creek, Cumberland County, New Jersey, Conrad; of Shiloh and Jericho, New Jersey, Burns; of Magnesia Spring, Alachua County, Florida, Burns. This species in its typical form is of a porous and vesicular texture, giving the extremely thick shell a surprisingly light weight. Specimens from the southern Eocene cited above have the same form and characteristics, but the usual dense and heavy shell of other oysters. These latter might be taken for exceptionally thick and senile specimens of O. trigonalis, which in that case would figure as the original stock of O. PErcrassa. This completes the list of positively Eocene species; the O. panzana Conrad (P. R. R. Rep., vii., pt. 1, p. 193, pl. 2, fig. 4, 1857 + O. pansa Conr. (err. typ.), 1866), which was doubtfully referred to the Kocene by Conrad, ts a perfectly unidentifiable species described from a worn and extremely obscure type now in the National Collection, but which probably belongs to a horizon later than the Eocene. Ostrea georgiana Conrad. O. georgiana Conr., Journ. Acad. Nat. Sci. Phila., rst Ser., vii., p. 156, 1834; Dana, Man. Geol., 1st ed., p. 519, fig. 811, 1863. O. contracta Conr., Rep. Mex. Bound., vol. i., pt. ii., p. 160, pl. 18, fig. 1, 1857. O. titan Conr., Proc. Acad. Nat. Sci. Phila., vi., p. 199, 1854; Pacific R. R. Rep., vi., p. 72, pl. iv., fig. 17 a; pl. v., fig. 17 @, 1857. Oligocene of the lower bed at Vicksburg, Mississippi, and Choctaw Bluff on the Alabama River, Alabama; also at Clarksville, Alabama, and Shell Bluff, Savannah River, Georgia; Miocene of Oyster Point, upper Rio Grande, near Roma, Mexico; Martinez, California; Roberts Ferry, near New Berne, North Carolina. TRANSACTIONS OF WAGNER 684 TERTIARY FAUNA OF FLORIDA The different names under which this gigantic oyster has been known are seen to be founded chiefly on geographical reasons as soon as the types are compared. The characters of the shell are all explainable by the effect of age and situs, so far as they differ from one another. The figuring of a typical specimen in Dana’s Manual has generally been overlooked. The typical O. georgiana are the enormous senile specimens with shells ranging to two feet long and three or four inches thick. The young and really more normal specimens have been overlooked, though much more abundant, or referred to other species, chiefly O. virginica, from which they differ by their more elongated, usually straight, deeply excavated cardinal area and the absence of .ribbing on the lower valve in most specimens. Ostrea georgiana, forma normalis. O. mauricensts Gabb (ex parte), Journ. Acad. Nat. Sci. Phila., 2d Ser., iv., p. 376, pl. 67, fig. 26, 1860. O. Bourgeotsii Rémond, Proc. Cal. Acad. Sci., p. 13, 1863; Gabb, Pal. Cal., 1., p. 33, pl. 11, fig. 57, 1869. O. Tayloriana Gabb, Pal. Cal., ii., p. 34, pl. 12, fig. 60, 1869. Oligocene of Shell Bluff, Savannah. River, Georgia; of Martin Station, Florida; White Sulphur Spring, Suwanee River, Hamilton County, Florida; six miles southwest of Gainesville, Alachua County, Florida; La Penotiere’s hammock, near Orient, Tampa, Florida; Nigger Sink, Newnansville; Devil’s Millhopper, near Hawthorne; Sullivan’s old field, Levy County; Johnson’s Sink, Levy County; Mage’s Springs, Alachua County; silex beds of Ballast Point, Tampa Bay; Rock Bluff, Appalachicola River, Calhoun County; red clay (so called Lafayette formation) over the Oak Grove marl, Santa Rosa County, Florida, and lower bed at House Creek, Georgia. Lower Miocene marl of Shiloh and Jericho, Cumberland County, New Jersey, and near Wilmington, North Carolina; Miocene of California and New Mexico. It is not unlikely that to the above synonymy should be added O. welen- zana Conrad (a typographical error for /e/enzana) of the Mexican Boundary Report, 1857, and the unrecognizable O. panzana and O. robusta Conrad, 1857. The O. Tryoni Gabb (1881), from the Miocene of Costa Rica, appears to be a well-characterized species. The young O. georgiana Conrad is the characteristic fossil of the Upper Oligocene of the Gulf States often found in northern Florida scattered over FREE INSTITUTE OF SCIENCE 685 TERTIARY FAUNA OF FLORIDA the surface of the Vicksburg limestone from which the Upper Oligocene marl has been dissolved away. It is the “leit fossil” of the Grand Gulf beds, though not confined to them, and occurs in the single meagerly fossiliferous bed below the Altamaha grits. The specimens are usually in poor condition superficially, having the exterior and often the interior vermiculately eroded. It occurs but rarely in the true Miocene, where it seems to become modified into the early type of O. wirginica, which is not improbably its direct de- scendant. In old Post-Pliocene beds or oyster reefs it is not uncommon to find enormously thickened senile specimens of O. virginica which present many of the features of the Oligocene O. georgiana. Ostrea haitensis Sowerby. O. haitensis Sby., Quart. Journ. Geol. Soc., vi., p. 53, 1850. O. haytensis Gabb, Trans. Am. Phil. Soc., 1873, p. 257. O. Veatchii Gabb, Pal. Cal., ii., p. 34, pl. 11, fig. 59, pl. 17, fig. 21, 1869. O. Heermanni Conr., Proc. Acad. Nat. Sci. Phila., v., p. 267, 1853; Pac. R. R. Rep., V., Pp. 326, 1855. O. vespertina Conr., Pac. R. R. Rep., v., p. 325, pl. 5, figs. 36-8, 1855 ; Gabb, Pal. Cal., ii., p. 107, 1869. (Young shell.) O. virginica Guppy, Quart. Journ. Geol. Soc., xxii., p. 577; not of Gmelin. O. virginica var. californica Marcou, Geol. N. Am., 1858. Oligocene of Haiti, of the Bowden marl of Jamaica, of the Chipola beds of Calhoun County, Florida, and of the Oak Grove marl, Santa Rosa County, Florida. Miocene (?) of Carrizo Creek, Colorado Desert, California, and of various other localities in California. Gabb recognized the identity of his O. Veatchw with the St. Domingo species, and a comparison of Carrizo Creek specimens adds the unfigured QO. Fleermanni to the list of synonyms. The O. vespertina was described from young shells from the types in the National Museum, and there can be no question of their identity. It is to be discriminated from its associated QO: Attwoodi, which has a smooth upper valve, by the fact that both valves are similarly plicated. Ostrea megodon Hanley. O. megodon Hanley, P. Z. S., 1845, p. 106; Reeve, Conch. Icon., Osévea, pl. xii., fig. 24 a—b, 1871. O. gallus Val., Plates of the Voy. Venus, Coq., pl. 21 (no text), 1846. O. cerrosensi?s Gabb, Pal. Cal., ii., p. 35, pl. 11, fig. 61, 1869. TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA Oligocene of St. Domingo and of the Bowden marl, Jamaica; Mio- cene (?) of Cerros Island, off Lower California; Post Pliocene of Lower Cali- fornia. Recent in the Gulf of California at Acapulco and southward. This is one of the types which were exterminated on the east coast of America by the disturbances which united the two continents and cut off access to both oceans, and which survived to the present fauna on the western side of the continent as united. It appears to be rare in the Oligocene, but the type is much older and is represented in the Cretaceous by O. falcata Morton. Ostrea carolinensis Conrad. O. carolinensis Conr., Fos. Tert. Form., p. 27, pl. 14, fig. 1, 1832. Eocene of South Carolina ? Miocene of the Santee Canal, South Carolina, Ravenel; and of the Choptank River, Maryland, Burns and Harris. The original reference of this species to the Eocene is probably erro- neous. The species, represented by some of the original Santee specimens in the National Collection, has only been definitely recognized from the Lower Miocene. It appears to be a sufficiently distinct species, nearly related to O. a7 gonalts. Ostrea sculpturata Conrad. ° O. sculpturata Conr., Medial Tert., p. 50, pl. 25, fig. 3, 1840. O. virginiana Conr., Fos. Tert. Form., p. 28, pl. 14, fig. 2, 1832; not of Lamarck. O. subfalcata Conr., Medial Tert., p. 50, pl. 25, fig. 2, 1840. O. virginiana Tuomey and Holmes, Pleioc. Fos. S. Car., p. 20, pl. 5, figs. 7-9 (fig. 6 excl.). } O. perlivata Conr., Kerr, Geol. Rep. N. Car., App., p. 18, 1875. O. meridionalis Heilprin, Trans. Wagner Free Inst. Sci., i., p. too, pl. 14, fig. 35, 35 2, 1887. Miocene of Coggins Point, Petersburg, Nansemond River near Suffolk, York River near Yorktown, and the north end of the Dismal Swamp, Vir- ginia; of Wilmington, Snow Hill, the Natural Well of Duplin County, Mag- nolia, Duplin County, and the Neuse River ten miles above New Berne, North Carolina; of Darlington, South Carolina, and De Leon Springs, Florida. Pliocene of the Waccamaw beds, South Carolina, and the marls of the Caloosahatchie, Shell Creek, and Alligator Creek, Florida. FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA Ostrea virginica Gmelin. O7 virginiana of Lister and other nonbinomial writers. O. virginica Gmelin, Syst. Nat., p. 3336, 1792; Dillwyn, Descr. Cat., 1., p. 277, 1817; Lam., An. s. Vert., vi., p. 207, 1819. O. edulis Akerly, Am. Monthly Mag., ii., p. 296, 1818 ; not Linné. O. virginiana Sby., Genera, Ostrea, f. 2, 1822. O. boreat’s Lam., An. s. Vert., vi., p. 204, 1819. O. canadensis Lam., op. ctt., p. 207, 1819. O. triangularts Holmes, Proc. Elliott Soc., i., p. 29, 1856. O. fundata Holmes, Post-Pl. Fos. S. Car., p. 11, pl. 2, fig. 10, 1858. ? O. semicylindrica Say, Journ. Acad. Nat. Sci. Phila., 1st Ser., i1., p. 258, 1822. Miocene of Cumberland County, New Jersey ? Pliocene of the Caloosahatchie and Myakka Rivers, Florida; Post Pliocene of the Atlantic and Gulf coasts from Prince Edward's Island to Florida, Texas, and California. Recent from Prince Edward’s Island south to Florida and west to Mexico, and on the west coast of Mexico near the head of the Gulf of California. This well-known species occurs positively in the Pliocene of Florida, but the Miocene citations require revision. Specimens from the New Jersey marls received from Professor Whitfield under this name were either O. georgiana mut. mauricensis or the young of O. percrassa. Most of the southern species thus named are better placed elsewhere. Say does not appear to have pub- lished any Os¢rea fundata, though the name has been used on his authority by Ravenel and Holmes. The long current-bred specimens, by confusion with those which have become elongated by mutual compression, have received the varietal name of procyon from Holmes. The same shell appears to be the O. rlizophore of Guilding and Reeve, though not O. rhizophora of Dillwyn. The O. furida Cpr. (1863) and O. palmula Cpr. (1857) with its variety conchaphila Cpr. (1857) are known from the Post Pliocene of the Pacific coast. I have not yet seen O. folium Linné or O. equestris Say, in the fossil state, on the east American coast. O. solea Conrad appears to be a mere list-name, never figured or de- scribed. O. Tuomeyt Coquand (Mon. Ostrea Terr. Crét., p. 68, 1869) was proposed for the preoccupied name of crenulata Tuomey, but Conrad had already used the specific name of Tuomeyi (1865) for a fossil oyster from Mississippi, so if the Coquandian fossil is a good species it will require a new name. TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA O. pandeformis Gabb, 1862, an unfigured, supposedly Cretaceous, species, is regarded as unidentifiable by Dr. C. A. White, but is considered by Aldrich to be Jacksonian and identical with O. Zuomeyi Conrad. It is, perhaps, from Aldrich’s remarks, a form of trzgonalis. Gryphea athyroidea Guppy (1866), from the Tertiary of Trinidad, appears to be a true Os¢rea and distinct from any of the continental species. I have not attempted to make comparisons with the European species, as that would require a series of the latter, which is not accessible, but a casual inspection of the figures does not give the impression that there are many of them which might be identical with American forms. Superfamily NAIADACEA. Famiry UNIONIDE. Genus UNIO Retzius. Unio (Unio) caloosaénsis n. s. PLATE 25, FIGURES 6, I2a. Pliocene marls of the Caloosahatchie River, Florida; Dall. Shell oblong-ovate, rounded in front, somewhat pointed at the ventral angle behind, umbonal region only moderately prominent, sculptured with numerous fine concentric wrinkles and seven or eight wavy, sharply elevated, narrow, concentric ripples; the latter are most prominent on the line of the posterior angle of the valves, on each side of which the ripple recedes, per- ceptibly making a small sinus, more conspicuous than any of the small fluctua- tions of the rest of the ripple; sides moderately compressed; ventral margin gently arcuate, straight, or slightly incurved just in front of the posterior angle which forms the ventral boundary of the posterior dorsal area; posterior end rounded above, slightly rostrate ventrally ; valves solid, nearly smooth, or with more or less irregular incremental sculpture and faint traces in some specimens of obscure radial lines near the posterior ventral angle; interior with strongly impressed pallial line and muscular impressions; “cardinal” teeth short, the ventral one usually stouter in the right and the dorsal in the left valve; laterals low, solid. Lon. 57, diam. 20, alt. 32 mm. This species, though usually defective, is not uncommon in the marls and sometimes with the valves in their natural position. The species belongs to the group of Unio Buckley? of the recent fauna, which is abundantly represented in the Floridian lakes. Having submitted it to Mr. Charles T. Simpson, who FREE INSTITUTE OF SCIENCE 689 TERTIARY FAUNA OF FLORIDA has made a specialty of these mollusks, he has expressed the opinion that it is undescribed. It is somewhat singular that this is the only Tertiary species of Unio known from east of the Mississippi in the United States. There are a number of Post-Pliocene species, including those from the New Jersey clays, which were long regarded as Cretaceous. Superfamily PECTINACEA. Famity PECTINIDZ. Genus PECTEN Muller. FPecten (Wein, 1753) Miiller, Prodr. Zool. Dan., p. 248, 1776; Da Costa, Brit. Conch., p. 140, 1778; Bolten, Mus. Bolt., p. 165, 1798; Lamarck, Prodr. d’un Nouv. Class. Coq., p. 88, 1799. Type Ostrea maxima Linne. The name /ecten is very ancient, and appears in the prelinnéan literature colloquially. Although Linné himself did not formally adopt it as a genus, he has used the term casually in some of his minor papers. It was first introduced into binomial literature by Miller. An excellent discussion of the characters of the group by Verrill appears in the Trans. Conn. Acad. Sci., vol. x., pp. 41-57, 1897. The genus has been repeatedly subdivided and the number of groups which have been named, chiefly on the shell characters of recent species, is very large. As might be expected, when the fossil forms are taken into consideration, the groups merge into one another by insensible gradations, and so far as I have been able to examine the anatomy the same is true of it also, while the minor differences of the gross anatomy do not appear to be at all strictly correlated with the superficial modifications of the shell. Like Conus, as demonstrated by Bergh, the Pectens seem to form a natural genus with a profusion of minor modifications, which may be separated for convenience into sections and subgenera, but possesses within certain general limits very uniform characters. The value of the named groups will differ with the personal equation of those who deal with them, but it appears impossible, when the fossils are included, to draw lines of generic demarca- tion which shall be clear-cut yet not in violation of nature. In various geological horizons, as well as in the existing fauna, certain species of Pecfen assume a sessile habit, involving an irregular subsequent growth of the valves after attachment to other objects, as in Afinnites. These species have no necessary genetic connection with one another except what they gain from their relations to the Pecteuzd@ as a group, and must be regarded as purely sporadic adjustments of individual forms to a particular environment. TRANSACTIONS OF WAGNER 690 TERTIARY FAUNA OF FLORIDA The shell of Pecten comprises two generally more or less discrepant valves, united along a long, straight hinge-line by an inconspicuous ligament and a central strong resilium. A single rounded adductor leaves its impression pretty high up, a little before the mesial line of the valves, and the pedal retractors are usually attached to the left valve above it, being often obsolete on the right side. The ends of the resilium are received by subtriangular or oval pits in the umbonal region. These pits may be shallow or deep; their basal margin sometimes projects slightly into the cavity of the valves; their apex is always nearly coincident with the umbonal point of the valve. Ina few species, in the right valve, the lateral margins of the pit are raised into tooth-like processes, which fit into corresponding depressions in the opposite valve (c.g, P. Swiftti Bernh.), but these are not homologous with the so-called teeth of Plicatula and Spondylus. Outside of these, radiating fan-like from the apex of the valve, are frequently found one to three pairs of more or less prominent laminz, which I call the cardinal crura, and further away and below, on the ridges which mark the lower boundary of the ears, will some- times. be found another pair, only distally conspicuous, which I have named the auricular crura. The cardinal crura are most conspicuous in heavy shells, especially such as /ecten proper and Lyropecten, and serve to adjust the closing of the valves, as does the hinge armature of the Teleodonts. In a few species the crura are sufficiently prominent to actually interlock with the valves half open; in many others hardly any trace of them is visible. Almost all species possess in the nepionic stage a well-marked provinculum, formed by an elongated area on each side of the pit, covered by long, narrow, close-set taxodont teeth, separated by narrow grooved interspaces. In most species the provinculum is evanescent or represented in the adult only by faint vertical striz, which cross the cardinal crura. In a few small, thin-shelled, mostly deep-water species, the provinculum is persistent and functional (¢. ¢., P. thal- assinum Wall), forming an interlocking hinge. In /ecten proper, Chlamys, and some other groups, the upper cardinal margin of the right valve is bent over that of the left valve. There are occasional species in which the adult valves have each a flat area along the whole cardinal margin, covered by the ligament and forming a V-shaped groove between the upper margins of the valves, as in P. Swéft. The disk of the valve is usually rounded or oblique below and at the sides, but above continued on each side ina straight line to the umbo. The shell adjacent to these straight lines is frequently slightly different in sculpture from the rest of the disk, forming narrow areas, which were called FREE INSTITUTE OF SCIENCE 691 TERTIARY FAUNA OF FLORIDA 5) by Conrad the “submargins.” Above the submargins the auricles, or ears, project, usually differentiated by a linear depression ending in a sinus below. This sinus is sometimes absent in the posterior ears, as it is in the very young stages of the shell, but it is not an important systematic character, since the same species (e. g., P. latiauritus Conr.) may exhibit varieties some of which have a well-developed posterior sinus while others are without it. The right anterior sinus is usually emphasized by a flexuosity in the lower edge of the ear above it for the accommodation of the byssus, and on the upper part of the submargin are usually found a number of small, regularly spaced spines, which in life separate the threads of the byssus and thus keep it from twisting with the motion of the water. The growth of the margin of the valve and ear does not always march with the development of these spines, so that a species which normally has them may exhibit stages when the valve margin has grown over the old set and the new set has not been formed, much like the inequalities of growth shown by the margin of the aperture and the internal liree of some Gastropods. This set of spines, resembling a short comb with curved teeth, has been called ctenolium, pectineum, and pectin- idium. In old very heavy shells, which are held in place more by their own weight than by the formation of a byssus, they are often absent, but may usually be traced in the groove corresponding to the younger stages, or fasciole, of the sinus. The swimming habit of Pecten is well known. It is more commonly exercised by the thin-shelled light or young individuals than by the heavier or adult specimens. The lateral ends of the ears do not close tightly. The valves being open, a quantity of water is retained between the inner laminz or “curtains” of the mantle, and the contraction of the adductor forces this water out between the submargins and through the cavity of the auricles, which impels the animal forward, the ventral margin of the valves being in advance as it moves. In this way the /Pecten moves quite rapidly with a jerking motion. In proportion to its surface the shell of Pecten is thin, and in the adult is usually ribbed or fluted, a condition brought about, doubtless, by natural selection and serving to strengthen the valves, which in swimming and falling on the bottom are subjected to rude shocks. When these flutings are formed in a thin shell, the interior is usually grooved in harmony with the ribbing of the exterior. To still further strengthen the shell at its weakest point, when the flutings are of angular section, a linear deposit of shelly matter is often Y) TRANSACTIONS OF WAGNER 692 TERTIARY FAUNA OF FLORIDA deposited on the angle internally, forming lire, coincident with the angle of the shell between the ribs and interspaces. This liration becomes habitual in some species. If then in the evolutionary progress of these forms it happens that the external ribbing becomes obsolete, the lirae may be retained by natural selection, as useful in strengthening the flattened disk, and thus we have the internal lire of Amuscum accounted for. It is not at all uncommon for ribbed species to have a smooth or obsoletely ribbed variety, and among the Eocene species here described is one which, within the species, shows every stage of the transition between a ribbed /ecfew and an internally lirate Amusium, thus rendering it impracticable to assign the latter group a system- atic value greater than that of a subgenus. The same thing may be observed in a good series of the recent P. hyalinus Poli. While the lire may appear without relation to any external sculpture in their final stage, there seems to be no doubt that, at the time of their inception, they were absolutely depen- dent upon a particular kind of external ribbing or fluting. In the obsolescence of ribbing the right anterior ear, probably because of strains resulting from the adjacent byssus making special strength necessary, usually is the last to lose its radial ribbing, and often retains it after the rest of the shell is practically smooth. Apart from the ribs or riblets, which usually cover the surface of the disk and ears, there are two other forms of external sculpture to be noted. One of these, originally supposed to be exclusively characteristic of the genus Camptonectes, is composed of fine, almost microscopic, more or less vermicular groovings, which radiate from the umbo and are deflected laterally from a mesial line of the disk. This is commonly known as the Camptonectes striation or sculpture, and is common to many recent forms, both ribbed and smooth. It is usually most conspicuous on the submargins, but often plainly visible in the smoother species (such as P. grdénlandicus) over the whole disk. The other type of sculpture, which may coéxist with any or all of the others, is a product of the minute concentric sculpture due to imbricated incremental lines. In Pectex proper the concentric sculpture is usually simple and sometimes (as in P. g¢ezac) almost absent. In P. maximus it takes the shape of minute regularly spaced concentric lamellz on the disk, but on the submargins and part of the ears this sculpture is often crowded and the distal edges of the lamella: more or less concrescent. In Chlamys, however, the most beautiful and complex surface-sculpture of this sort is found. The lamellz are elevated, and at points corresponding to a FREE INSTITUTE OF SCIENCE 693 TERTIARY FAUNA OF FLORIDA minute radial line give out little linguiform projections. Often these alternate on adjacent radials and, their distal edges being concrescent, a reticulated cellular sculpture results. This may be still further modified by minute differences of the radials, and finally the distal edges may become completely concrescent, hiding all the cellularity below. By erosion, when still alive, the last stage may be and usually is lost almost completely; it is more commonly preserved in fossil than in recent specimens. The paleontologist may find, according to the vicissitudes his specimen has undergone, (1) the concrescent surface alluded to; (2) the reticular cellularity of the lamella which have lost their upper surface; (3) the mere tracery of the bases of the lamella, the walls of the cells being gone; or (4) the surface completely smooth from wear and yet not obviously eroded. Great care is necessary, therefore, not to be misled into describing as different structures which origin- ally were identical. The original prototype of VPecten, judging from the stages of recent shells and the succession of the fossils, was a thin, nearly smooth shell, with a taxodont provinculum and the posterior ears ill-defined. Many sculptured Pectens begin their career in this form. Subsequently the ribbed species with cardinal crura were developed. Next ribbing became obsolete in more seden- tary species. The left valve, being that most in contact with other objects, retained the radial sculpture longest. Species inhabiting soft ooze and depths where motion of the water is feeble and infrequent, or defended by a situs among the arborescent corals or other safe nooks, finally lost the radial sculpture altogether or only retained the internal lire. The disparity of sculpture between the two valves observable in many deep-water Pectens is perhaps accounted for by the fact above mentioned that the left valve retained the ribs longer than the right valve, and, secondly, that flexibility in the ventral edge of the right valve (incompatible with radial ribbing) became use- ful in excluding the impalpable mud of great depths by its more hermetic sealing of the valves. Consequently, the concentric sculpture of this valve, which is inherent in its mode of growth, alone survived. The most modern type of Pecten is doubtless Azmusiun. That it is derived from a ribbed form is shown by some of the Oligocene species which have (like A. Lyon Gabb) a nepionic ribbed stage. I believe this group of forms is chiefly sedentary, as the shell and relatively feeble adductor are not suited to rapid motion and the violent shocks involved in this mode of progression. The peculiar hood-shaped form of the distal part of the foot is better suited TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA 694 to act as a sucker or scoop-anchor, by which the animal might drag itself about, than as a stilt or vaulting-pole, as in some of the shallow-water species. The discrepancy in size of the valves appears to be more or less related to the activity of the animal. The species in which the difference is greatest are probably the more sedentary. In nearly all sessile Pelecypods the lower valve is deeper, and the differences in the Pectens are probably due to the same factors of the environment. In nearly all the species the right valve is the least inflated. In a few, which are among the most active swimmers (like P. zvradians Lam.), the right valve is more convex than the left. It does not seem to be a feature of system- atic importance, as species otherwise apparently nearly allied differ in this respect. The influence of the environment is very marked among the Pectens. As in mammals and birds, the same species in the northern part of its range is larger than in the south, unless it is a distinctively tropical species. But in color the rule is reversed, the southern specimens being lighter and more brightly tinted than the northern ones in the same species. The specimens which live in deep water and swim actively are usually thinner-shelled and smoother, while those which inhabit the lagoons are heavier, have more con- spicuous concentric sculpture, and more solid shells. These differences are very marked in our common east coast P. zradians, of which P. dislocatus Say is the southern lagoon form; and parallel differences appear in the similarly related P. ventricosus and its variety @guisulcatus, on the Pacific coast, and in the fossil P. eboreus and comparilis of the Carolina Tertiaries. Whatever might be advisable were our knowledge of the Pectinide con- fined to the recent species, any paleontological division of them cannot ignore the intergradation which is so obvious between the different types, of which the extremes appear so unlike. For this reason the subdivisions adopted here will be comparatively few, and their rank such as belongs to groups obviously connected by intimate intergradations of peripheral species. They may be arranged as follows: Subgenus Pecten s.s. Type P. maximus L. Left valve moderately inflated, right valve flattish; sculpture of strong ribs with radial striation, more or less roughened by simple concentric lamella- tion or incremental sculpture ; ears subequal. Section Euvola Dall, 1897. Type P. ziczac L. Left valve extremely inflated, surface polished, ribs moderate or obsolete, FREE INSTITUTE OF SCIENCE 695 TERTIARY FAUNA OF FLORIDA x without radial striation, concentric sculpture inconspicuous; right valve with or without conspicuous radial and concentric sculpture, flat or concave. Subgenus Ch/amys Bolten, 1798. Type P. zslandicus Mill. Valves moderately inflated, subequal, in general similar (except in color); sculpture of radial ribbing with or without Campéonecfes striation, with or without an imbricate surface layer; frequently spinose on the ridges; ears often discrepant, the posterior smaller. Section Lyropecten Conrad, 1862. Type P. estrellanus Conr. Shell resembling Pecten s. s., but with both valves convex; usually of large size, heavy, and with radial striation and minute concentric imbrication ; ribs entire and not dichotomous; valves equilateral. Section Placopecten Verrill, 1897. Type P. Clintonius Say. Valves without ribs, the right smoother, the radial and concentric minor sculpture of Lyropecten persisting ; ears subequal; valves equilateral. Section Patinopecten Dall, 1898. Type P. caurinus Gld. Valves with small ribs, flat on the right valve and sometimes dichotomous ; smaller and more rounded on the left valve; concentric sculpture inconspicu- ous; radial striz absent or obsolete; ears subequal; valves nearly equilateral. To this group belong such fossil species as P. Meekw Conrad and P. expansus Dall. Section Modipecten Dall, 1898. Type P. nodosus L. Shell like Lyvopecten, but the ribs intermittently nodose, with more or less prominent hollow nodes or bulla; radial striation pronounced; ears unequal, the posterior smaller, the valves often more or less oblique; imbricate surface layer sometimes very marked. Section Chlamys s.s. Type P. islandicus Miller. Ribs small and numerous, imbricate or spinose; valves subequal, similar, oblique, or with unequal ears, the posterior smaller; Camptonectes striation and imbricate surface layer usually present; shell usually solid and opaque ; byssal notch and ctenolium present. Section Aguipecten Fischer, 1887. Type P. opercularis L. Shell thin, orbicular, with subequal inflated valves, usually equilateral, with uniform, well-marked radial, not dichotomous, ribs and finely imbricate radial striation; ears subequal; valves internally lirate on the edges of the TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA 696 grooves corresponding to the external ribs; Camptonectes striation present, but usually obscured by the radial sculpture; ctenolium and byssal notch obvious. Section Plagioctenium Dall, 1898. Type P. ventricosus Sby. Resembling Zguzpecten but without radial striation; the concentric sculpture in looped lamellae; the ribs strong, frequently smooth above; the submargins impressed below the subequal auricles; the valves well inflated with a tendency to oblique growth in the adult. To this very natural group belong nearly all the shallow-water Pectens of our own coasts, such as P. wrradians Lam., P. gibbus L., P. dislocatus Say, P. ventricosus Sby., P. nucleus L., P. purpuratus Lam., P. eboreus Conrad, P. comparilis T. and H., and numerous other fossil species. Section Palium Schum., 1817. Type P. plica Lam. ~ Shell with the disk high and narrow above, ears srnall; valves moderately inflated, nearly similar, the basal margin in the adult contracted, so that the edges meet each other nearly vertically; ribs few, large, widening distally, entire; surface radiately imbricately striate, frequently with Camptonectes striation and. imbricate external layer; the cardinal crura usually well developed, often irregular. The developed cardinal crura are a function of the short hinge-line and of little systematic importance; their regularity is usually exaggerated in the ficures. Pecten pallium Lis more appropriately placed in the Ch/amys section. In the typical species of this group the most peculiar features are the perfectly closed valves, the margins meeting all around the shell, the absence of a byssal notch or fasciole, and the obvious tendency of the irregular cardinal crura to be discrepant on the two sides of the resilial pit. Some specimens have very regular laminz like those of most laminate species, in others the anterior laminze show a tendency to break up into nearly vertical narrow folds. These features are apparently confined to the less normal specimens of this species and should hardly form the basis for systematic rank. Fecten pana- mensis Dall, which has in most respects an unusually close resemblance to P. plica, differs by having the cardinal laminz obsolete and in the presence of a byssal sinus and ctenolium. In fact, the interchange of characters is so multi- farious that one must, to be consistent, either propose a genus for every two or three species of Pectew or include all the species in one generic group. Locard, who adopts the former method, has proposed the name Fe/ipes for a FREE INSTITUTE OF SCIENCE 697 TERTIARY FAUNA OF FLORIDA closely allied group with P. pesfelis L. as the type; and Bucquoy, Dautzen- berg, and Dollfus (1889) propose Peplum, with P. clavatus Poli as type, which would include such species as P. panamensis; and Sacco adds Hexopecten (1897) for P. flexuosus Poli, which differs by having larger ears. Subgenus Pseudamusium A. and A. Adams, 1858. Type Pecten exoticus Chemn., = P. pseudamusium (Klein) Sby. Shells small, thin, more or less translucent; the sculpture, if any, feeble ; inner face of the disk without lirae; disk with or without Camptonectes stria- tion, frequently with concentric imbrication. Section Pseudamusium s.s. Type P. pseudamusium Sby. (= exoticus Chemn., etc.). Sculpture discrepant on the two valves, the right valve having the con- centric, and the left valve the radial elements most pronounced ; valves usually flattish or compressed. The type is a shallow-water species and shows bright colors; the species from deep water are frequently pale or whitish. The latter have been separated as Cyclopecten by Verrill. Section Camptonectes (Agassiz MS.) Meek, 1864. Type P. /ens Sby. Shell similarly sculptured on both valves, more or less inflated; smooth, con- centrically more or less undulated, divaricately striate, or delicately imbricated. The minute features of surface sculpture are so interchangeable and so variable that I cannot regard them as having sectional, much less generic, value, at least in the sense in which the term is used in this work.* Though Camptonectes was originally based on the character of the divaricate striz, the species in which this character is obsolete must be included, unless violence is to be done to what seems close relationship. Syncyclonema Meek, if correctly made out by that careful author, has a com- pletely closed shell without a byssal notch, the ears subequal, the left valve smooth, the right concentrically striated. * Professor Verrill proposes for the smooth form Pecfzvel/a ; for the undulated form Hyalopecten ; the divaricately sculptured shells would then be typical Camtonectes; the imbricated ones like P. vitreus | (Gmelin, 1792) Dillwyn, 1817 (++ aczlearus Jeffr., 1843, 4+- abyssorum Loven, + gemellaro-filit Biondi) not P. vitreus Gray, 1824 (= P. gronlandicus Sby., 1843); P. vitreus Risso, 1826; P. vitreus King, 1831 (= P. corneus Sby., 1843), nor P. vetreus Shy., 1843] would be Palliolum Monts. (restr.), 1884. Zdburneopecten Conrad, 1865, based on P. scznéz//atus Conr., is an exact synonyme of Camptonectes. Lissochlamis Sacco (1897) is founded on P. excisus Bronn (non Pusch), a species unknown to me. TRANSACTIONS OF WAGNER 698 TERTIARY FAUNA OF FLORIDA Until more is known, this section would best be retained. It is doubtful how important the characters of Lytolium Meek (1864) may prove to be. Lissopecten Verrill (1897) based on P. hyalinus Poli seems to me merely a somewhat degenerate quipectcn. Leptopecten of the same author is based on the kelp-inhabiting variety of P. (Chlamys) latiauritus Conrad; its peculi- arities result directly from its special situs; the shells intergrade perfectly with the other chlamydoid forms. Subgenus Amuszum Bolten, 1798. Type P. pleuronectes L. Valves flattish, internally lirate, externally usually smooth or faintly striated; ears subequal; the ctenolium absent and the byssal notch obsolete. Pleuronectia Swainson, 1840, is synonymous. Section Amusium s.s. Type P. pleuronectes L. Valves about equally convex, gaping at the sides, nearly similar in sculp- ture, the recent forms having the left valve darkly colored and the right valve pale or albescent. Amusium Lyon Gabb in the youthful condition has a sculptured left valve like Propeamusium. Section Propeamusium Gregorio, 1883. Type P. tnequisculptus Tiberi (= fenestratus Forbes). Right valve impressed about the distal margin, which is not fully calcified, partially concave, the sides partially closed, away from the ears; the lire shorter; the external sculpture chiefly concentric, while on the left valve, if present, it is radial; the recent forms usually glassy or pale colored in both valves. On anatomical grounds Professor Verrill separates, as Paramusium, Amu- sium Dali Smith; but there are no distinctive conchological characters. In the Bulletin of the Zoological Museum of the University of Turin, No. 298, pp. 101-2, June 11, 1897, Sacco has given a list of subdivisions of FPecten, without definition, but referring to the species he regards as types, or includes under the several subgenera. Among those not above mentioned are the following: Under the genus Amusium, of which P. cristatus Bronn is regarded as typical, Parviamussium Sacco (1897) is typified by P. duodecimla- mellatus Bronn, and Vartamussium Sacco (1897) by P. cancellatus “ Schmidt” (? Goldfuss, not Bean and Phillips or McCoy), while P. fenestratus Forbes is included. This section is therefore a synonyme of Propeamusium de Gre- gorio, 1883. FREE INSTITUTE OF SCIENCE 699 TERTIARY FAUNA OF FLORIDA Pecten burdigalensis am. (regarded by Deshayes as a variety of the species cristatus Bronn, referred to Avzusiwm by Sacco) is made type of a sub- genus of typical Pecten called Amusstopecten by Sacco, and the subgenera Oépecten Sacco, based on Pecten rotundatus Lam., and Hadbellipecten Sacco, on P. flabelliformis Brocchi, are also referred to typical Pecten. If differential descriptions of new groups were imperative, probably some of the above might never have seen the light, but, with present methods, the flood of new names is likely to continue unchecked by any considerations drawn from a serious study of nature. Subgenus /zznites Defrance, 1821. Type . Cortezi Defr. Shell (up to advanced youth) a typical Ch/amys, later becoming sessile and irregular, in which stage the resilial pit is elongated and the cardinal margin develops an obscure area. Y/znnita Gray is synonymous. There are several groups of Pectinzd@ in Paleozoic and Mesozoic horizons, as well as one or two exotic recent types, which do not need to be considered here. FOSSIL PECTENS OF THE PACIFIC COAST. Since it became absolutely necessary to review the Pacific coast and Antillean Pectinid@ in order to settle the status of those of the Atlantic coast, and as this review has necessitated a good deal of hard work, and the results may be useful to the student, a synopsis of them is offered here. Pecten (Patinopecten) propatulus Conrad. Pecten propatulus Conrad, Geol. Wilkes Expl. Exped., App. 1, p. 726, pl. 18, figs. 13, 13.2, 1849. Pecten cauryinus of various authors, but not of Gould. Astoria Miocene of the Columbia River; Dana. The types of this species are in the National Museum. It has been regarded as identical with P. caurinus Gould by Carpenter, Cooper, and others, but, as pointed out by Meek (Miocene Checklist, S. I. Misc. Coll., p. 26, 1864), while the recent shell has from twenty to twenty-six ribs and a minutely con- centrically striated surface, the P. propatulus rarely has more than sixteen ribs, and when perfect has the surface microscopically tessellated. The latter is also a generally smaller and more convex species. Pecten (Patinopecten) Meekii Conrad. LPecten Meekiz Conr., Pac. R. R. Rep., vii., p. 190, pl. 1, fig. 1, 1857. Miocene of San Rafael, California; Conrad. TRANSACTIONS OF WAGNER 700 TERTIARY FAUNA OF FLORIDA The type specimen of this species is also in the National Museum, and it is much closer to P. cawrinus than the last species. It has twenty ribs and, except that it is somewhat more convex, closely resembles P. caurzmus in every respect when of the same size. The latter, however, has not yet been found in the succeeding Pliocene deposits, though present in the fauna of Puget Sound. Conrad’s figure is a mere caricature. Pecten (Patinopecten) coosensis Shumard. PLATE 26, FIGURE 2. Pecten coosensits Shumard, Trans. St. Louis Acad. Sci., i., pt. 2, p. 122, 1858. P. coosaénsts Meek (err. typ.), 5. I. Mioc. Checkl., p. 3, 1864. Miocene of the Empire beds (Astoria horizon) at Coos Bay, Oregon; Shumard and Dall. This species is large, compressed, with twenty-nine to thirty-one squarish prominent ribs, and on the upper valve much wider interspaces crossed by fine incremental lines. The ribs are sometimes longitudinally grooved towards the base. Specimens are in the National Museum and measure in alt. 120, lat. - 113, and diam. 27 mm. This fine species is very abundant in the locality indicated. It is nearest to the Pliocene P. expansus Dall, in which the ribs are dichotomous. Pecten (Chlamys) altiplicatus Conrad. Pecten altiplicatus Conr., Pac. R. R. Rep., vii., p. 191, pl. 3, fig. 2, 1857. Pecten altiplectus Cony. (err. typ.), Proc. Acad. Nat. Sci. Phila. for 1856, p. 313, 1857. Pecten hericeus Carpenter, Cooper ; not of Gould. Miocene of the San Rafael hills near Santa Barbara, California; W. P. Blake. This species, which is wretchedly figured by Conrad, is represented by the type in the National Museum. It has ten or eleven high, sharp spinulose ribs alternated with an equal number of low, small imbricate riblets, the inter- spaces sculptured with elevated radial scabrous threads. The beak and ears are defective, but the typical specimen is characteristic enough to show that it is entirely distinct from the recent Pecten hericeus Gould, with which it has often been doubtfully united. P. catilliformis Conrad (op. cit., v., p. 329, pl. 9, fig. 83, 1856), which resembles in the figure a flattened valve of P. Heermanni seen from within, and P. nevadanus Conrad (of. cit., p. 329, pl. 8, fig. 77) were described from drawings made by Professor W. P. Blake from internal or external casts in the FREE INSTITUTE OF SCIENCE 701 TERTIARY FAUNA OF FLORIDA sandstones of Ocoya Creek. No types of them exist, and the figures are so bad that it is to be feared they will remain for a long time unrecognized. Section Lyrvopecten Conrad. Lyropecten Conr., Proc. Acad. Nat. Sci. Phila. for 1862, p. 291; Meek, Smithsonian Checkl. Mio. Fos., pp. 5, 27, 1864. Type Pal/ium estrellanum Conr., Pac. R. R. Rep., vi., Geol., p. 71, pl. ili., fig. 15, 1856; Proc. Acad. Nat. Sci. Phila., viii., p. 313, 1857; Liropecten estrellanum Cooper, Bull. State Mining Bur. Cala., No. 4, pl. 6, figs. 65-67, 1884 (text excl.). Not P. estrellanum Conr. of Pac. R. R. Rep., vii., p. 191, pl. 3, figs. 3-4, = P. voleformis Conr., Proc. Acad. Nat. Sci. for 1862, p. 291. Liropecten Gabb, Pal. Cal., ii., p. 105, 1869. Not Lyvopecten Conrad, Am. Journ. Conch., iii., p. 6, 1867. Type P. crassicardo Conr., Proc..Acad. Nat. Sci. Phila. for 1862, p. 291. Not Lzvopecten Fischer, Man. de. Conchyl., p. 944, 1887. Type P. nodosus Linné. Not Lyropecten Vernill, Trans. Conn. Acad. Sci., x., p. 63, 1897. Type P. zodosus Linné (following Fischer). Not Lyriopecten Hall, 1883, —section of Aviculopecten. Among the types of the Pacific Railway explorations is a fossil Pecten with a label “ Estrella Valley” in Conrad’s handwriting. The ears have been broken off, but in other respects it agrees well with the description and figure of Pallium estrellanum. The ribs are worn flat, and the undulations mentioned in the description are due to erosion. It is the only specimen agreeing at all closely with the requirements, and I have no doubt it is one of the specimens from which Conrad’s description was prepared. Better preserved fragments show the intercalary line clearly, and also that the ribs were imbricated, as in P. Jeffersonius, by minute elevated scales. It is, in short, a Pecten belonging to the same group as P. Jeffersonius, Madtsonius, crassicardo, etc. Curiously enough, the same specimen served as the subject for Conrad’s PR. Heermanni (Proc. Acad. Nat. Sci. Phila., vii., p. 267, 1855), described in a line and a half and never figured. The two were identified by Conrad as the same species on the National Museum labels. In the confusion that surrounds the specific name estrellanum (three species of Pecten from the same region having been so named by Conrad), it is probably better to revert to the earlier name of Fleermanni. A fair figure, cited above, has been given by Cooper. The type of the second form, named estrel/anum, is lost. It appears to have been a shell resembling Pecten dentatus Sby. in outline, but the sculpture and number of ribs agree with the original estre/lanus. Conrad renamed it LZ. voleformis, but the difference of shape may be due to crushing, as the fossils TRANSACTIONS OF WAGNER 702 TERTIARY FAUNA OF FLORIDA of this horizon are all more or less distorted, and the shell may be the same, as he originally thought it to be. The dentition of the hinge is similar to that of many Pectens, such as P. Szzftzz2 Bernhardi, P. ventricosus Sby., and P. purpuratus Lam. The third species referred by Conrad to this group is P. magnolia Contr. (Pac. R. R. Rep., vii., p. 191, pl. 1, fig. 2, 1857), of which the very imperfect fragments which served as types are in the National Museum. The figure is a very erroneous diagram compounded from the characters of these fragments. A better specimen of the same species was later described by Conrad under the name of ZL. crasstcardo (Proc. Acad. Nat. Sci. Phila. for 1862, p. 291) but has not been figured. The types are in the Academy’s collection. Both valves are convex and have the hinge-teeth moderately developed. The shell has from eleven to fourteen ribs and much resembles P. /effersonius, except in the greater development of the hinge-teeth and the radial ribbing of the ears. It grows even larger than the average /effersonius and belongs to the Miocene of the Santa Inez Mountains, Santa Barbara County, California. According to Gabb (Pal. Cal., ii., p. 105) a broken specimen of this species ~ served as the original for the figure of Spondylus estrellanus Conr. (Pac. R. R. Rep., vii., pl. 1, fig. 3, 1857), an opinion which the figure, poor as it is, offers much to confirm. The genus established by Conrad was based on the heavy cardinal laminze which compose a distinctly dentiferous hinge; this feature, however, varies in the different species and is insufficient as a basis for a group of such value in view of its inconstancy. The group name, whatever rank is assigned to it, must depend upon the type. This, as already pointed out, belongs among those species which unite with sculpture similar to that of P. maximus the character of having both valves more or less convex, instead of having the right valve flattened or even subconcave. Such shells are more or less inter- mediate between Aiguipecten Fischer and Pecten proper. In 1867 Conrad, with the forgetfulness which marked his later work, produced the genus Lyropecten again, as if it was not already described, and offers as a type L. crassicardo, one of his original species but not that origi- nally indicated as the type. ZL. crassicardo, however, is a true member of the croup. But to this species he adds Pecten nodosus and its allies, which are not entitled to be admitted. Fischer, in citing Conrad, ignores the original description and mentions P. xodosus as the type, which it never was, and thus subsequent writers were led into error. The modification of the original FREE INSTITUTE OF SCIENCE f 793 TERTIARY FAUNA OF FLORIDA orthography by Gabb and Fischer is unnecessary and contrary to the rules of nomenclature followed in this volume. Notwithstanding the fact that the real type is intermediate in form between the P. ventricosus group and that of P. /effersonius, the balance of characters is decidedly in favor of the latter, and, thus restricted, it forms a fairly natural and recognizable assembly which will contain, besides the type, such forms as P. crassicardo Conr., P. Jeffersonius Say, P. Madisonius Say, P. edgecombensis Conr., P. septenarius Say,—all large species, with conspicuous ribbing, radially squamose-striate surface, convex and nearly equilateral valves, and more or less developed cardinal laminze. The group is chiefly Miocene. In Pecten Clintonius we have a species which appears to differ remarkably from such forms as /effersonius, and yet the most essential distinction is the absence of ribbing. If we were to imagine a specimen of P. /effersonius with the ribs flattened out, the distinction between it and P. Chntonius would be almost imperceptible. In recent Pectens the group is only represented by such forms as P. fuscopurpureus Conrad, which never attain a large size but resemble in their sculpture the young shell of P. Madisonius and its allies. They can hardly be accommodated in the group as here restricted. Pecten (Plagioctenium) deserti Conrad. Pecten deserti Conr., Pac. R. R. Rep., v., p. 329, pl. 8, fig. 77, 1856; Descr. Fos. and Shells, House Reps. Doc. 129, p. 15, July, 1855. Pecten discus Cooper, Cal. State Min. Bur. Bull., No. 4, p. 57, pl. 4, figs. 55, 56, 1894 ; not /. discus Conrad, 1857. Miocene (?) of Carrizo Creek, Colorado Desert. This appears to be a well-defined species resembling P. curgidus Lamarck, having twenty-three close-set, smooth, rounded, prominent ribs, and both valves moderately convex; the specimens are usually crushed. This has been confounded by Cooper with P. discus Conrad, his remarks showing that Dr. Cooper is unacquainted with the true P. discus. Pecten (? Plagioctenium) pabloénsis Conrad. Fecten pabloénsis Conr., Pac. R. R. Reps., vi., p. 71, pl. 3, fig. 14, 1857. Miocene of San Pablo Bay, California; Merriam. This species is represented by a better figure than some of the others, and has been collected from the original locality by Dr. John C. Merriam, of the University of California. It has been erroneously referred to the TRANSACTIONS OF WAGNER 704 TERTIARY FAUNA OF FLORIDA young of P. estrellanum (= Heermanni Conr.) by Dr. Cooper. It is small, with feeble sculpture like a young, pressed-out Pecten propatulus, with eighteen to twenty major ribs alternated with smaller intercalary riblets. The ears are discrepant, the right anterior one radially ribbed. The shell measured about thirty millimetres in height and length. Pecten (Pecten) bellus Conrad. Janira bella Conrad, Pac. R. R. Rep., vi., p. 71, pl. 3, fig. 16, 1857. Not Janira bella Gabb, Pal. Cal., i1., p. 105, pl. 16, fig. 20, 1868. Not Pecten bellus Shy. (ubz ?), nor P. bellis McCoy. Tertiary of Santa Barbara, California. Neither the description nor the figure are sufficient to positively identify this shell, of which no authentic specimen is known. Such information as is given does not agree with either of the recognized species. Pecten (Chlamys) fucanus n. s. PLATE 26, FIGURE 7. Found in concretions from the Miocene sandstones of Clallam Bay, twenty-five miles eastward from Cape Flattery, on the south shore of Fuca Strait, Washington, by Mr. J. S. Diller, of the United States Geological Survey. Another specimen was received from J. G. Swan, collected in the same vicinity. This is a rather large species of the type of P. Aindst var. strategus, both valves moderately convex and with a fine subsidiary surface tessellation ; sixteen squarish ribs, of which the median one in the left valve is stronger than the rest and surmounted by prominent imbricated scales; the others are simply radially striated, as are the interspaces, which carry a mesial elevated thread; the submargins are radially threaded, as are the subequal ears, which also bear marked concentric lamella; the resilial pit is of moderate size and the cardinal edge is deeply grooved parallel to and just below the margin; the interior reflects the external ribbing. Alt. 85, lat. 80, convexity of left valve 16 mm. Types in the National Museum. This interesting form is represented by very perfect internal and external casts of the left valve and other less perfect examples. It is doubtless the precursor of the recent P. hericeus group. Pecten (Chlamys ?) discus Conrad. ecten discus Conrad, Pac. R. R. Rep., vii., p. 190, pl. 3, fig. 1, 1857; not of Cooper, Cal. State Min. Bur. Bull., No. 4, p. 57, pl. 4, figs. 55, 56, 1894. FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA 795 From the fine-grained Miocene shales of Santa Barbara County, Cali- fornia. This is a beautiful thin, flat species, resembling a young Patznopecten, but more oblique and oval, the left valve showing nine or more low, wide, smooth ribs in the middle of the disk, with wider smooth interspaces, and the sculp- ture obsolete towards the ends and base of the valve; the right valve has narrower, sharper, smaller, and more numerous riblets; the left valve meas- ures about forty-seven millimetres in height and width, and the shell was apparently about ten millimetres in diameter; the ears are plain and unequal. Conrad’s figure is very poor and gives little idea of the shell. This may belong to the section gupecten. Species which may be of Miocene or Pliocene age and were collected on Cerros Island, Lower California, were described by Gabb (Pal. Cal., ii., p. 32, 1866). P. cerrosensis Gabb (of. cit., p. 32, pl. 9, figs. 55, 55 2) has eighteen to twenty flattish, entire ribs, with about equal interspaces. It is of the type of P. eboreus Conr., but much larger. P. Veatchit Gabb (of. cit., p. 32, pl. 10, fig. 56) is of the general type of P. zodosus, and has about fourteen feebly nodose broad ribs, striated, reticulated, and minutely squamose. The little, smooth P. Peck- hami Gabb with Camptonectes striation (Pal. Cal., ti., p. 59, pl. 16, figs. 19, 19 a, 1866) and the concentrically undulated P. pedroanus (Trask) Gabb (Plagiostoma pedroana Trask, Proc. Cal. Acad. Sci.,i., p. 86, pl. iii., fig. 1, 1856; ++ P. annulatus Trask, /oc. cit., fig. 2, and P. truncata Trask, fig. 3; Gabb, Pal. Cal., ii., p. 60, 1866) comprise the remaining species of the Pacific coast, which are supposed to be of Miocene age. Some of them may also prove of Pliocene age. The following undetermined forms have been observed in the collection of the State University at Berkeley, California : Pecten sp. A species in the State University collection at Berkeley, Cali- fornia, which had been marked P. pabloénsis by Dr. Cooper is evidently distinct; it has fifteen primary ribs on the left valve, many of them unevenly divided near the basal margin by a shallow sulcus; in the interspaces are low, rounded riblets, extending about half way up the disk; right valve some- what more convex; the ears subequal and vertically striated. Alt. 85, lat. go mm. Found in the Miocene of Foxin’s Ranch, California. FPecten Heermanni Conr. var.? A large species from Santa Inez Cafion, Santa Barbara County, California, is biconvex, with sixteen large, nearly smooth ribs in the right valve, with subequal interspaces, in the middle of each of which is a single small raised thread; ears subequal, the posterior TRANSACTIONS OF WAGNER 706 TERTIARY FAUNA OF FLORIDA radially and the others concentrically threaded; the left valve somewhat less convex. Alt. 145, lat. 147, extreme length of hinge-line 80 mm. Pecten sp. San Pablo formation, Mount Diablo, Contra Costa County, California, has fourteen to sixteen ribs, strong and simple, with narrower chan- nelled interspaces, which, as well as the ribs in some cases, are radially striated; ears subequal, somewhat impressed, with a few rather coarse radial riblets and concentric striation. Alt. 127, lat. 137, hinge-line 70 mm. Pecten sp. A small species recalling P. descrti was collected near Mount Diablo; it is rounded, moderately convex, with eighteen to twenty slightly nodulous subequal ribs, with channelled equal interspaces crossed by fine looped concentric sculpture; the shell is like a small @guzsaulcatus in general form, with small subequal ears. Alt. 28, lat. 28, hinge-line 18 mm. Pecten sp. indet. The flat valve of a species, in poor condition, but re- calling P. dentatus Sby., has been received from Miocene beds near San Diego. The following are of Pliocene age: Pecten (Patinopecten) expansus Dall. PLATE 26, FIGURE I. ecten expansus Dall, Proc. U. S. Nat. Mus., i., p. 14, 1878. Pliocene of Pacific Beach (lower horizon), near San Diego, California ; Hemphill, Dall, and Hamlin. Shell large, flattish, with, on the right valve, twenty-five to thirty flat dichotomous ribs, which differentiate it from the other species of this group. Pecten (Pecten) Stearnsii Dall. PLATE 26, FIGURE 5. Pecten Stearnsit Dall, op. cit., p. 15, 1878. Found with P. expansus. This is the Pliocene precursor of Pecten diegensis Dall, from which it differs by having five or six more ribs, which, in the adult, have a conspicuous median sulcus. Pecten laqueatus Sby., a Japanese species, has been erroneously cited by Reeve from California. Pecten (Pecten) Hemphillii Dall. Pecten Hemphillit Dall, op. cit., p. 15, 1878. Janira bella Gabb (non Conrad), Pal. Cal., i1., pl. 16, fig. 20, 1869; not P. bella Shy., nor P. bellis McCoy. FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA Te Found with P. expansus. This shell is probably identical with the /Janzra bella of Gabb, but it differs from the original /. de//a Conrad by its entire ribs, rounded above instead of square, with extremely fine concentric lamellation. Pecten (Pecten) compactus n. s. PLATE 34, FIGURE 5. Pliocene of Ventura County, California, at an elevation of two hundred feet and eight miles inland from the sea; U.S. Nat. Mus., No. 61,246. Shell having a general resemblance to fecten dentatus Sby. and P. Poulsoni Morton, being slightly larger than the latter and sculptured more like the former. Right valve with twenty flat-topped, entire, smooth, squarish ribs, separated by much narrower channelled interspaces, crossed by faint incremental lines; submargins smooth except for incremental lines ; posterior ear with six or seven faint minute radials crossed by elevated lines of growth; byssal ear small, with three or four conspicuous subimbricate radials and a rather small notch and ctenolium; internal basal margin fluted; hinge-teeth rather strong. Alt. 27, lat. 27, diam. of left valve 8 mm. Pecten (Plagioctenium) subventricosus n. s. PLATE 29, FIGURE 8. Pliocene of Ventura County, California, Bowers; and of Pacific Beach at San Diego, Stearns and Hemphill. Shell of the type of P. ventricosus Sby., from which it differs by being smaller and less tumid, less expanded laterally, with the ribs rounded, instead of flattened, above, and with narrower interspaces; the tops of the ribs smooth, the sides with a dense fringe of concentric lamella, much as in com- paris T.and H. Alt. and lat. 65, diam. 24 mm. Pecten (Chlamys) opuntia n. s. PLATE 29, FIGURE 6. Pliocene of San Diego, California; Hemphill and Hamlin. Allied to P. hericeus var. navarchus Dall, from which it differs by its smaller and not fasciculated radial ribs, more elongated anterior ear, more densely radially costate posterior ear, small size when adult, and by a tendency to be suddenly contracted at. the basal margin on the completion of growth, somewhat as in P. pesfelis, Alt. 35, lat. 32.5 mm. 10 TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA NI O ioe) Pecten (Chlamys) Parmeleei n. s. PLATE 37, FIGURES 14, 14 @. Pliocene of San Diego, California; Parmelee. This species is close to P. Sz2/tz Bernhardi of Japan (J. de Conchyl., vii., plates 1 and 2, 1858) but smaller, and differs by the smooth top surface . of the ribs, which in P. Szezftz are more or less striated or coarsely threaded, and by the not alternated radial riblets on the right posterior ear; also, especially, by the profuse coalescent microscopically checkered squamation, which makes a complete external coating to the valve. Alt. 45, lat. 38 mm. ‘The Pecten fauna changes almost completely with the Pleistocene, all the species being known as recent and generally of the same climatic groups as those at present living in the most adjacent waters. The following species have been noted : Pecten (Chlamys) islandicus Miiller. Pecten islandicus Mill., Prodr. Zool. Danica, p. 248, 1776. Pecten cinnabarina Born, 1778, + P. rubidus Martyn, 1784, + Ostrea demissa Solander, 1797, + Lecten Pealett Conrad, 1831, + P. Habrice Philippi, 1844. Bowlder clays of the northwest coast, also living in Bering Sea; Dall. Ribs numerous, subequal, rounded, small, scaly on both valves, with channelled minutely reticulate interspaces. Pecten (Chlamys) hericeus Gould. Pecten hericeus Gould, Proc. Bost. Soc. Nat. Hist., p. 236, 1850. ecten hastatus Cpr., 1863; not of Sowerby, 1843. ? = FPecten rastellinum Val., Voy. Venus, pl. 19, fig. 4, 1835. Pleistocene of San Diego, California; Hemphill. Middle ribs of the fasciculi on the left valve high, spiny, the rest merely scaly. This is entirely distinct from the true P. hastatus Sby., with which Carpenter confused it. The latter is a smaller, quite rare shell, with entirely different sculpture, and has not yet been found in the fossil state. I have taken the name of Gould, as the oldest, for the specific designa- tion of a group of forms of which the original /ericews is only a special development, the prevalent and normal form of the species being the follow- ing shell: Pecten hericeus var. navarchus Dall. Pecten rubidus Hinds, Zool, Sulph. Voy., p, 61, pl. 17, fig. 5, 1844; not A. rudbedus Martyn, 1784, FREE INSTITUTE OF SCIENCE ae ; 799 TERTIARY FAUNA OF FLORIDA Bowlder clay of Comox, Vancouver Island, Newcombe; Pleistocene of San Pedro, Dall and Stearns; of San Diego, California, at Pacific Beach, Hamlin. Smaller than P. ¢slandicus; ribs small, obscurely fasciculated, dichoto- mous, and imbricated on both valves. Living from the Aleutian Islands south- ward to Lower California. Pecten hericeus var. Hindsii Carpenter. Pecten (2 var.) Hindsiz Cpr., Suppl. Rep. Brit. Assoc., p. 645, 1863. Pleistocene of Sucia Island, Fuca Strait, Newcombe; recent from Bering Sea to Monterey, California. Ribs on the right valve smooth, not fasciculated, sometimes wide, flattish, usually dichotomous; left valve as in var. zavarchus. The typical specimens seem remarkably distinct from xavarchius, but in a large series intergradation is obvious. Pecten hericeus var. strategus Dall. Pleistocene of Alaska and recent at Unalashka; Dall. The fasciculi of the left valve, to the number of five to seven, with the riblets coalescent, forming large, smooth-backed, turgid ribs, with smaller imbricate intercalary threads. The large ribs sometimes break up suddenly into the usual small riblets near the base. The recent specimens are bright scarlet. Pecten (Chlamys) latiauritus Conrad. Pecten latiauritus Conrad, Journ. Acad. Nat. Sci. Phila., vii., p. 238, pl. 18, fig. 9, 1838. Pecten tunica Phil., 1844 +- P. mesotimerts Sowerby, 1847. Pecten tumbezensts Orbigny, 1847, + P. aspersus Sby., 1843, non Lam., 1819, + P. Sowerbi Reeve, 1852 (non Guilding), is very closely related. Pleistocene of San Pedro Hill and San Diego at Coronado Beach; very abundant. Also living. Hinge-line wide; the ears acutely pointed above; ribs distinct, squarish, often mesially grooved; shell wide. This is the type, which varies widely. Pecten latiauritus var. monotimeris Conrad. P. monotimeris Conrad, op. cit., p. 238, pl. 18, fig. 10, 1838. Shell more oblique, inflated, and markedly shorter, with smaller ears. Found with the last, with which many specimens intergrade, TRANSACTIONS OF WAGNER 710 TERTIARY FAUNA OF FLORIDA Pecten latiauritus var. fucicolus Dall. With the last, and living on fuci, south to Cape St. Lucas. Shell moderately compressed, smooth, concentric, sculpture obsolete; ribs low, rounded, wide, entire; hinge-line shorter than in the type, and without any sinus between the posterior ears and the disk. Alt. 30, lat. 31 mm. This form lives attached by the byssus to the giant kelp of the Californian coast, and the absence of shock, due to the floating situs, is probably cor- related with the obsolescence of the ribs and posterior sinus. Intergradations with the type are not at all rare. Pecten (Patinopecten) caurinus Gould. Fecten caurinus Gould, Proc. Boston Soc. Nat. Hist., p. 236, 1850. fecten yessoensts Cpr., 1863, non Jay, Perry’s Voy., 1856, + P. propatulus Carpenter, 1863, non Conrad, 1849. ? Pecten Meeckit Conrad, Pac. R. R. Rep., vil., p. 190, pl. 1, fig. 1, 1857. ? Miocene of California, Blake; not yet reported from the Pleistocene of California, but will probably be found in later beds of Puget Sound and vicinity when fully explored. Living about Puget Sound. The Japanese species is constantly distinguished by its smaller and lower ears and deeper byssal sinus. Pecten (Nodipecten) subnodosus Sowerby. — Lecten subnodosus Sby., P. Z. S., 1835, p. 109. Lecten intermedius Conrad, Am. Journ. Conch., iii., p. 7, 1867. Pleistocene of Cerros Island and other points on the Lower Californian coast. Living in the adjacent waters. There seems to be little reason for separating this form from the P. nodosus of the Antilles. Both vary through a strictly analogous series of mutations. : Pecten (Pecten) diegensis Dall. Fecten floridus Hinds, Zool. Sulph. Voy., p. 60, pl. 17, fig. 6, 1844; not Ostvea (= Pecten) florida Gmelin, 1792. E Pleistocene of San Diego; Hemphill. Living on the adjacent shores from Monterey, California, southward. Pecten (Plagioctenium) ventricosus Sowerby. LPecten ventricosus Sby., Thes. Conch., Pecfen, p. 51, pl. 12, figs. 18, 19, 1843. Pecten tumidus Sby., P. Z.S., 1835, p. 109; not P. tumzdus Turt, 1822, nor of Zieten, 1830. Pecten ciycularis Sby., ex parte, 1835 ; 4- P. mca Orb., 1847. g ?— Lecten pomatia Val., Voy. Venus, pl. 19, fig. 3, 1835. FREE: INSTITUTE OF SCIENCE 711 TERTIARY FAUNA OF FLORIDA d Pleistocene of San Pedro, San Diego, and Lower California; Hemphill, Stearns, and Orcutt. Living from.Santa Barbara southward. This species is the Pacific coast analogue of P. dslocatus Say. Pecten (ventricosus var.?) eequisuleatus Cpr. Pecten equisulcatus n. s.? Carpenter, Suppl. Rep. Brit. As., 1863, p. 645; Ann. Mag. Nat. Hist. Mar., 1865, p. 179. Found with the preceding. This form bears to wventricosus precisely the relation which P. trradians Lamarck, on the Atlantic coast, bears to P. dslocatus Say. Pecten (Propeamusium) alaskensis Dall. Pecten alaskens?s Dall, Am. Journ. Conch., vii., p. 155, pl. 16, fig. 4, 1871. Pleistocene of Vancouver Island, near Esquimalt, and at various points in Alaska. Living from Bering Sea to Panama Bay, usually in deep water. This species has twenty to twenty-two internal rib-like lire. There is a small species of Propeamusium resembling P. sguamula Lam. in the Arago beds of Oregon, but the exterior is not yet known. It is prob- able that a fair number of additions to this list may be made when the different horizons of the Pacific coast are sufficiently explored. Pecten pyxidatus, which has been listed from the Pacific coast, is apparently a Chinese species. P. swbcrenatus Carpenter and P. Townsend: Gould seem to be list-names, cited in Carpenter’s supplementary report to the British Asso- ciation in 1865, but never characterized and now unidentifiable. Subgenus HINNITES Defrance. flinnites Defr., Dict. Sci. Nat., xxi., p. 169, 1821. Type 4. Cortezz Deft. Lfinnita Ferussac, Tabl. Syst., p. xl., 1822. Ffinnus Wood, Ann. Mag. Nat. Hist., xxxvii., p. 253, 1841. Hinnites crassus Conrad. Flinnites crassa Conr., Pac. R. R. Rep., vii., p. 190, pl. 2, figs. 1, 2, 1857. ?—= Ffinnites giganteus Gray, Ann. Phil., p. 103, 1826. Cf. Pecten comatius Val., Voy. Venus, pl. 18, fig. 2, 1835. Miocene of Santa Margarita, Salinas Valley, California. It should be mentioned that Hinzztes giganteus Gray (Ann. Phil., 1826, + H. Poulsoni Conr., 1834) is not uncommon in the Pleistocene, and the young d shells, which sometimes reach the length of thirty millimetres before becoming TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA 712 attached to other bodies, are in fact Pectens, and very liable to be taken for an undescribed species of that genus. They are variable in the amount of spinose sculpture, and the more spiny ones often closely resemble the young of the true Pecten hastatus Sby. Inthe recent specimens a character by which they can usually be discriminated is a suffusion of purple color on the hinge- line near the cartilage-pits. FOSSIL PECTENS OF THE ANTILLEAN AND CENTRAL AMERICAN REGION. Nearly all of these species are Oligocene; a few are referable to the Pliocene; but the typical Miocene or Chesapeake fauna has not been identi- fied anywhere south of Florida. The first species described from this region appear in the paper by Sowerby on the Bowden fauna in 1849. As a number of these were very briefly described and never figured, I sent a series of the Bowden Pectens in the National Museum to Mr. Clement Reid, of the British Geological Survey, who very kindly compared them with Sowerby’s types and furnished me with valuable annotations upon them. In the small series available for study the range of variation necessarily remains doubtful in some cases, though I have had the advantage of comparing with the series of types in the Guppy collection of Antillean fossils now the property of the United States National Museum. It appears from Mr. Reid’s examination that the type specimens are not segregated in the Sowerby-Heniker collection, that the fossils are loose in trays, and these trays sometimes contain more than one species. The confu- sion has probably occurred since Sowerby’s time, as he was a very careful worker. Under these circumstances the reviser can only take the form which is best in accordance with the original diagnosis and restrict Sowerby’s name to it. Pecten (Pecten) soror Gabb. Janira soror Gabb, Trans. Am. Phil. Soc., xv., p. 257, 1873. Oligocene of St. Domingo, Gabb; of Jamaica and Cumana, Guppy. A large species with twenty rounded, strong ribs, separated by flattish interspaces, with fine concentric elevated lines, the flat valve also strongly ribbed, the right valve very convex, and the shell a little inequilateral. Pecten (Pecten) eugrammatus n. s. PLATE 34, FIGURE 22. Oligocene of Haiti and St. Domingo, Guppy. FREE INSTITUTE. OF SCIENCE TERTIARY FAUNA OF FLORIDA Shell suborbicular, convex, with twenty-one high, sharp ribs separated by V-shaped narrower interspaces, the ribs with a sharp but shallow mesial sulcus and the outer edges of the sulcus sharp and flaring; submargins smooth, ears radially threaded, inner margin deeply fluted; surface with fine, low, sharp concentric lamellae when perfect; notch small, narrow, sharp, with no cteno- lium ; cardinal crura well developed, sharply cross-striated; ears small. Alt. 23, lat. 24, diam. 8 mm. This species may possibly belong to guipecten, but its aspect is that of Pecten. Ihave not seen the left valve. There is an unnamed valve of this species in the Heniker collection. Pecten (Kuvola) bowdenensis n. s. PLATE 29, FIGURE I. Oligocene of the Bowden beds, Jamaica; Henderson and Simpson. Shell resembling P. zczac L. in the right valve, with about twenty-three obsolete smooth ribs separated by impressed lines; right valve very convex; ears subequal, smooth, notch narrow, deep; left valve with seventeen low, rounded ribs separated by wider, squarely impressed interspaces ; submargins wide, smooth; disk moderately concave; ears subequal, smooth, concavely arched; interior margin of the base with paired lira, the pairs separated by deeper channels; cardinal crura obvious. Alt. 43, lat. 44.5 mm. The sculpture of the left valve definitely separates this species from the young of P. ziczac, P. medius, and allied forms known from this region. Pecten (Huvola) limonensis Dall. Janira levigata Gabb, Journ. Acad. Nat. Sci. Phila., 2d Ser., viii., p. 379, 1881; not Fecten levigatus Goldfuss, Petref., ii., p. 68, pl. 97, fig. 6, 1835. Pliocene clays of Limon, Costa Rica; Gabb. Pecten (Aiquipecten) oxygonum Sowerby. Fecten oxygonum Sby., Quart. Journ. Geol. Soc., vi., p. 52, 1849. Pecten angusticostatus Gabb, Geol. St. Dom., p. 256, 1873. Pecten exasperatus Guppy, Geol. Journ., xxil., p. 294, 1866. Oligocene of St. Domingo, Gabb; and Jamaica at Bowden, Henderson and Simpson. Shell small, suborbicular, with nineteen to twenty-one sharply keeled ribs separated by V-shaped interspaces, with little-elevated, sharp, thin, con- TRANSACTIONS OF WAGNER 714 TERTIARY FAUNA OF FLORIDA centric linear imbrication; form tumid, cardinal crura well marked; left valve less convex than the other. Alt. and lat. about 15 mm. The above diagnosis is from the type of P. angusticostatus, and agrees with Sowerby’s diagnosis. The shells which are now found under the name of Sowerby in the Heniker collection are, according to Mr. Reid, a pair (A) which are orbicular, suboblique, not tumid, with a well-marked small rib in each furrow, coarsely squamose sculpture, and a height of forty-seven and a half millimetres. The other specimen (B) is a single valve with the rib in the furrow obsolete or absent, the shell oblique, surface coarsely squamose. The two are not certainly the same species, and both of them conflict in character with Sowerby’s diagnosis. I cannot accept them, therefore, without further evidence, as being the originals. Specimen A recalls strongly the shell here named P. Gadi, and may be a specimen of that species which has been acci- dentally labelled with a name not belonging to it. In case this view is not accepted, in spite of the discrepancies between the specimen and Sowerby’s description, the present form will take Gabb’s name. Pecten (Afquipecten) inzequalis Sowerby. Pecten mequalts Sby., op. czt., p. 52, 1849; Guppy, Geol. Journ., xxil., p. 294, pl. 18, fig. 6, 1866. Oligocene of St. Domingo and Haiti, Gabb; Jamaica, Bland; Curagao, United States Fish Commission; Isthmus of Darien, Hill. This much resembles P. angusticostatus Gabb in form.and size, but the ribs are rounded and the interspaces roundly concave. It is the most common and widely distributed of the Antillean Oligocene Pectens. Pecten (Atquipecten) thetidis Sowerby. Pecten thettdis Sbhy., op. cit., p. 52, 1849. Oligocene of St. Domingo, Heniker; Bowden, Jamaica, Henderson and Simpson ; Curagao, United States Fish Commission. This is a shell much resembling the recent Florida shell which Conrad named fuscopurpurcus, but the latter is larger and less solid. The specimens in the Heniker collection include two indeterminable valves: (A) four tumid, inequilateral, equivalve, with nineteen sharp ribs and sharp furrows, sculpture squamose; (B) one orbicular compressed valve with nineteen ribs which are markedly quadrate at the margin, squamose and wrinkled, but scarcely spiny, the ribs of the disk and those of the wing forming a nearly continuous series. FREE INSTITUTE OF SCIENCE Wi TERTIARY FAUNA OF FLORIDA 7*5 Mr. Reid remarks that Sowerby’s description was apparently mainly drawn from B, and that the two forms are so distinct that it is difficult to believe that Sowerby can have referred them to the same species. In the absence of a figure we may adopt B as representing the name, which would agree with usage as seen in the Guppy and other collections. The other specimens (A) seem from the remarks cited to be nearest to some varieties of oxygonum or inequals. Pecten (Aiquipecten) scissuratus n. s. PLATE 34, FIGURE 4. Oligocene of Ponton, St. Domingo, and ten and a half kilometres west of Colon, Isthmus of Darien; Hill. Shell moderately compressed, with sixteen well-marked ribs; valves nearly equilateral, the right one less flat than the other; disk suborbicular, with small subequal ears; left valve with the ribs smooth and rounded on top, separated by subequal, slightly channelled, smooth interspaces; the ribs on each side just below the top are incised by a sharp, narrow groove, in which are closely set small imbricated scales, which seem easily detached, so that in the worn specimens the sulcus alone remains, ending in a narrow, sharp slit at the distal end of the rib; the ears are flat, with sparse radial threads; in the right valve the ribs are squarish and smooth, the sulci are absent, and the surface sculpt- ure confined to faint incremental lines; the ears have a few imbricate radii, and the notch is shallow; the submargins are narrow and young shells have a polished surface; the internal surface is channelled in harmony with the ex- ternal ribbing; the auricular and cardinal crura moderately developed. Alt. 31, lat. 30, diam. about 6 mm. In young shells the sulci on the ribs are not conspicuous, and in perfect ones the scales must more or less completely hide the grooves. Pecten (Chlamys) anguillensis Guppy. Pecten anguillensis Guppy, Proc. Sci. Soc. Trinidad, Dec., 1867, p. 175. Oligocene of Anguilla and Antigua; Guppy and Spencer. This is quite closely related to the recent P. antillarum Recluz, of which it is evidently the precursor, and also resembles P. /uculentus Reeve. Pecten (Chlamys) ornatus Lamarck? var. vaginulus Dall. Oligocene of the Bowden beds, Jamaica; Henderson and Simpson. Seven small valves of a species closely resembling P. ornatus were TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA 716 obtained at Bowden; the form and sculpture are practically the same, but the ribs (twenty-one to twenty-five) are single, subequal, and not fasciculated, and are separated by simple narrower interspaces not radially threaded. The young of ovnatius, as far as observed, seem to always have one or more inter- stitial riblets. I therefore propose for the present form the varietal name ot vaginulus, which may be raised to specific rank if the difference is confirmed by the characters of adult specimens. Pecten (Chlamys) interlineatus Gabb. Pecten interlineatus Gabb, Geol. St. Dom., p. 256, 1873. Oligocene of St. Domingo; Gabb. Shell close to P. anxguillensis Guppy, with about sixteen flattish, eroded ribs, with narrower interspaces containing a single thread; the surface sculp- tured with fine, wavy, concentric lamellz; posterior two or three ribs under the byssal notch are corrugated on the anterior edge; submargins narrow, the anterior smooth; ears subequal, radially sculptured, notch deep. These notes are taken from the types of this unfigured species in the collection of the Academy of Natural Sciences, Philadelphia. This may prove to be identical with the specimen now standing as the type of P. oxygonum Sby. in the Heniker collection. Pecten (Chlamys ?) sp. indet. Pecten opercularis Gabb, Geol. St. Domingo, p. 256, 1873 ; not of Linné. Oligocene of St. Domingo; Gabb. This is a nearly smooth, ovate-oblong shell, with twenty-two nearly obsolete ribs, fading out at the submargins; ears small, low, subequal. Alt. 7o, lat. 58mm. It is obviously not the European species with which Gabb too hastily identified it. Pecten (Chlamys) cactaceus n. s. PLATE 34, FIGURE 2. Tertiary of St. Domingo, Gabb; Pliocene of Tehuantepec, seventy kilo- metres west of eastern terminus of the railway, near the foot-hills of the elevated country, Spencer. Shell thin, fragile, compressed, nearly equilateral and equivalve, with ten to twelve sharp, narrow-keeled ribs, with much wider shallow interspaces, in which there are five or six fine, sharp radial threads; whole surface, when FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA : perfect, covered with imbricating scales, those on the ribs triangular, apices basally directed, and similarly on a smaller scale, on the threads, between the keels and threads the imbrication is looped in an umbonal direction, sharp and rasp-like ; ears subequal, with close, sharp, concentric, elevated lines and a few subspinose radial threads ; interior grooved in harmony with the external ribs ’ the margins of the channels reinforced by lirze in the adult; crura developed notch shallow. Alt. 47, lat. 46, diam. about 8 mm. This is quite a distinct species, not particularly like any other described from this region and apparently a deep-water.shell. The specimens in Gabb’s collection are mixed with others identified by him as oxygonum Sby., and their horizon is not definitely settled. Pecten (Nodipecten) nodosus Linné. Pecten nodosus Linné (as Ostrea), Syst. Nat., No. 164, 1758. Pecten magnificus Gabb, Geol. St. Dom., p. 256, 1873; from type, not of Sowerby, 1835. Oligocene of St. Domingo, Gabb (? Pliocene); Pliocene of Florida and the Antilles, Willcox. Living in the Antillean region. The shell named magnzficus by Gabb is merely one of the less nodose mutations of this well-known and variable species. Pecten (Plagioctenium) excentricus Gabb. Pecten excentricus Gabb, Geol. St. Dom., p. 256, 1873. Oligocene of St. Domingo; Gabb and Bland. Shell small, oblique, with about twenty-one low ribs, narrow and flattened on top, with subequal interspaces, both crossed by sharp, looped concentric lamellae; submargins smooth, ears small, with sparse radial lines; auricular crura pronounced, cardinal crura strong, with sharply incised cross-striation. This recalls a young specimen of swbventricosus. Pecten (Plagioctenium) Gabbi Dall. PLATE 29, FIGURE 3. Pecten paranensis Gabb, Journ. Acad. Nat. Sci. Phila., 2d Ser., viii., p. 347, pl. 45, fig. 24, 1881 ; not of Orb., Voy. Am. Mer. Pal., p. 135, pl. vii., figs. 59, 1849. Oligocene of Antigua, Spencer; and of St. Domingo, Gabb. Shell broad, compressed, oblique, inequilateral, with nearly equal valves and about nineteen concentrically scabrous, longitudinally striated ribs, with narrower interspaces, each filled with one imbricated riblet. Alt. 48, lat. 52, diam. 13 mm. TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA 718 The Antillean species is quite distinct from that figured by Orbigny, and more nearly resembles his P. ¢ehuelchus, which has a more inflated and rounder shell, with a much larger and less oblique posterior ear. (Cf. Voy. Am. Mer., Mollusques, pl. 85, figs. 21 to 24.) Pecten (Plagioctenium) demiurgus n. s. PLATE 26, FIGURE 3. Pecten comparilis Guppy, Geol. Mag., Dec. ii., vol. i., p. 451, 1874; not of Tuomey and Holmes, 1855. (rom types.) From the Caroni Series of Trinidad at Savanetta; Guppy. This species, which is closely related to the Pacific coast P. ventricosus Sowerby, differs by its rounded and minutely squamose’ ribs, narrower um- bones, wider and less inflated shell, with the anterior ears more deeply inset. It has twenty ribs, smooth submargins, and a rather deep notch. Alt. 70, lat. 2, max. diam. 36 mm. The left valve is a little less inflated than the other. Pecten rudis Gabb, as of Sowerby, from the Tertiary of Costa Rica, appears to be indeterminable. Pecten (Pseudamusium) Guppyi n. s. PLATE 34, FIGURES 12, 13. Oligocene of the Bowden marl, Jamaica, and of the Alum Bluff sand at Oak Grove, Santa Rosa County, Florida, Burns; and in the Pliocene marl of Port Limon, Costa Rica, Hill. Shell small, suborbicular, moderately convex, smooth, with the surface covered with microscopic Camptonectes striation; ears small, the anterior slightly larger, all with very minute radiation and concentric lines; notch narrow, small, with no ctenolium ; interior smooth, without liree or developed crura; traces of the auricular crura alone perceptible; cardinal margin bearing a sharply cross-striated, very distinct provinculum; basal margins flattened, posterior margin slightly compressed. Alt. 6, lat. 6 mm. The abundance and uniformity of this little shell testify to its adult character. Occasional individuals show a thickened line internally on each side, on the lower edges of the submargins, like some recent species, and also traces of coloration in blotches. Amusium papyraceum Gabb. Pleuronectia papyracea Gabb, Geol. St. Dom., p. 257, 1873. 2? = Amusitum Mortont Ravenel, 1844. Oligocene of Bowden, Jamaica, Henderson; and of St. Domingo, Gabb. FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA 719 This species when young is more ovate, when adult orbicular. The um- bones are smooth, by which it may be instantly distinguished from P. (Ama- sium) Lyont. ‘Whether it can be separated from Azzzszum Mortont Rav. or not will depend upon comparisons for which the material at my command is as yet insufficient. The species is still living in Antillean and Gulf waters. Alt. 50, lat. 55 mm. F Amusium Lyoni Gabb. Pleuronectia Lyont Gabb, Journ. Acad. Nat. Sci. Phila., 2d Ser., viil., p. 347, pl. 45, fig. 25 a-6, 1881. Pecten Mortont Guppy, op. czt., p. 451, 1874. Oligocene of Anguilla, Guppy; of Bowden, Jamaica, Guppy; Pliocene of Tehuantepec, Spencer; and of Costa Rica, Gabb. This form, otherwise very similar, is immediately distinguishable from P. (A.) papyraceus by the nepionic sculpture of the umbonal region. Most of the recent Pectixide of the Gulf and Antillean region are found associated with other recent shells in the raised beaches and reefs so numer- ous on the islands. It is not necessary to enumerate them here, but I may mention that Pecten (Euvola) ziczac L. is quite abundant in the Pleistocene of Barbados. FOSSIL PECTENS OF THE FLORIDIAN REGION. The environs being now cleared, we may proceed to consider the species represented in the Floridian horizons and the adjacent portions of the south- eastern United States. Pecten (Pecten) Poulsoni Morton. fecten sp. Lesueur, Walnut Hills Fos., pl. 5, figs. 3, 4, 1829. fecten Poulsont Morton, Syn. Org. Rem., p. 59, pl. xix., fig. 2, 1834. Pecten elixatus Conrad, Proc. Acad. Nat. Sci., il., p. 174, 1846. Janira promens de Gregorio, Mon. Claib., p. 181, pl. 21, figs. 17-25, 1890. Oligocene (Vicksburgian) at Vicksburg, Carson’s Creek, Wayne County, and Shubuta, Mississippi; near Rosefield, Louisiana, Vaughan; near Archer, Florida, Dall; at Jarves Spring, Florida, Willcox. Abundant in the Vicks- burgian beds generally, but hitherto frequently confused with P. perplanus Morton. This is a very solid and characteristic little shell. The ribs in young specimens are often simple; in adults they are apt to take on two or three longitudinal grooves. The crura are strong and well developed. TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA Pecten (Pecten) biformis Conrad. ecten biformis Conrad, Proc. Acad. Nat. Sci. Phila., i., p. 306, 1843; Fos. Med. Tert., p- 73, pl. 42, fig. 1, 1845. Eocene (?) of the Pamunkey River, Virginia; Conrad. This rare and little-known species has the nepionic part smooth, or obso- letely radially striated. There are five or six original ribs; the succeeding riblets are numerous, rough, irregular, and minutely imbricated; the left valve is concave, otherwise like the other. Alt. 26, lat. 25 mm. The type speci- mens, which are all I have seen, have a somewhat abnormal aspect, and it would not be surprising if the sudden change in the sculpture should prove to be an exceptional feature. The horizon is also a little doubtful, and the species may turn out to be Miocene when its true situs is identified. Pecten (Pecten) Burnsii n. s. PLATE 34, Ficure 8. Oligocene of the Chipola marls, Chipola River, Florida; Burns. Shell resembling P. Poulsont Morton, but smaller, less inflated, and with larger ears; ribs fourteen, on the right valve strong, each divided by two grooves so as to be tricarinate, the minor keels scabrous, the interspaces nar- rower, with fine concentric sculpture; ears and submargins radially threaded, the ears large, subequal, the notch shallow; left valve flat, the ribs angular, simple, strong, with fine concentric sculpture; ears large, radially finely threaded; interior fluted. Alt. 18, lat. 19, diam. 6 mm. In specimens of P. Poulsoni of the size of this species the scabrous tri- carination of the ribs has not yet appeared; they are quite simple, and number seventeen to twenty. This is probably one of those cases where a lineal descendant takes on the adult character of the ancestor at an earlier period in its life than the ancestor did, a character often indicating senility in the life of the species. P. Lurnsit appears to be rare, and the type disappears entirely from the succeeding horizons, as far as known, being replaced in the Miocene by large species such as P. hemucyclicus, Pecten (Pecten) Humphreysii Conrad. fecten FHumphreysi Conr., Bull. Nat. Inst., i., p. 94, pl. 2, fig. 2, 1842. Pecten Humphreysti var. Woolmanz Heilprin, Proc. Acad. Nat. Sci. Phila., 1887, p. 405. Miocene of the Plum Point horizon, at Plum Point, Centreville, Burch, and other localities in Maryland; older Miocene of Cumberland County, New Jersey, at Shiloh and Jericho, and of Virginia and South Carolina, FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA “NI iS) = This fine and rare species is somewhat widely distributed. The variety Woolmant, which differs from the type by its more sharply striated surface and pronounced sculpture, is chiefly known from the New Jersey localities. Pecten (Pecten) hemicyclicus Ravenel. Janira hemicyclica Ravenel, Tuomey and Holmes, Pleioc. Fos. S. Car., p. 25, pl. 8, figs. I-4, 1855. FPecten hemicyclus Meek, S. 1. Checkl. Mioc. Fos., p. 4, 1864 (err. typ.). Newer Miocene of Cooper River, South Carolina, at the Grove, and on Goose Creek at Smith’s; Ravenel and Holmes. This fine species differs from the other American forms in its size and _ close, coarse concentric sculpture, recalling P. maximus of Europe, but of a more inflated form. Pecten (Pecten) Raveneli n. s. PLATE 29, FIGURE Io. Rare in the Pliocene of the Caloosahatchie marls, Florida, Dall; dredged, with other fossils, off Cape Fear, North Carolina, in fifteen fathoms by the United States Fish Commission. Shell much of the size and form of P. medivs Lam., but with twenty-one or twenty-two strong ribs; dichotomous in the right valve but rounded and simple in the left, with three or four finer threads on the submargins; inter- spaces on the right valve smaller than the squarish ribs, on the left subequal ; right valve with subequal ears, each with three or four strong, rounded riblets; notch shallow; ears of the left valve concave, two-ribbed, with less pronounced sculpture; surface of both valves covered with close-set, concentric, elevated lines; interior fluted, crura moderately developed. Alt. 42, lat. 47, diam. 13 mm. - This neat little species differs from P. medius in its coarser sculpture, and from the young of P. hemicyclicus by its more numerous ribs and details of surface, Pecten (Huvola) Holmesii Dall. Janira afinis T. and H., Pleioc. Fos. S. Car., p. 26, pl. 8, figs. 5, 6, 1855 ; not of Reuss, 1846, nor Risso, 1826. Miocene of South Carolina, on Goose Creek, at Smith’s. This fine species is only known by the author’s types now in the American Museum of Natural History, New York City. The name em- ployed was already in use for a Cretaceous species of Europe by Reuss, and TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA for a recent species from the Mediterranean by Risso, so I have substituted another. Pecten (Lyropecten) Jeffersonius Say. Pecten Jeffersonius Say, Journ. Acad. Nat. Sci. Phila., 1st Ser., iv., p. 133, pl. 9, fig. 1, 1824 ; Conrad, Fos. Medial Tert., p. 46, pl. 22, fig. 1, 1840. Miocene of the Nansemond, James, and York Rivers, Virginia, at Suffolk, City Point, Coggins Point, Bellefield, and Grove Wharf; also in the Miocene of North Carolina. Pecten Jeffersonius var. edgecombensis Conrad. Pecten edgecombensis Conrad, Proc. Acad. Nat. Sci. Phila. for 1862, pp. 291, 581, 1863. Liropecten carolinensis Conrad, in Kerr, Geol. N. Car., App., p. 18, 1875 (from type). Miocene of Coggins Point, Petersburg, Grove Wharf and Gaskins Wharf, York River, and Suffolk, Virginia; Langley’s Bluff, Maryland, and near Tarboro’, Edgecombe County, North Carolina. Pecten Jeffersonius var. septenarius Say. Pecten septenarius Say, Journ. Acad. Nat. Sci. Phila., 1st Ser., iv., p. 136, pl. ix., fig. 3, 1824. Pecten septemnarius Conrad, Med. Tert., p. 47, pl. 22, fig. 2, 1840. Miocene of St. Mary’s River, Maryland; Petersburg, Virginia; Duplin County, North Carolina, and the Peedee River, South Carolina. Rather rare. It is probable that no group of Pectens shows more interestingly the factors of variation in sculpture than that comprising the east American Lyro- pectens. These shells (L. Jeffersonius and Madisonius) illustrate the different muta- tions in the most instructive way. They are ribbed shells, nearly equilateral and equivalve, with a surface sculpture of fine radial scabrous threads. It is probable—since the range of /effersonius is more restricted and its earliest appearance in the Miocene, while M/adisonius is represented by precursors in the Oligocene—that /effersonius is an offshoot from MJadzsonius and that P. Clintonius, even, may be another. To determine the range of variation in the matter of the primary ribs, I have counted them on all the specimens in the collection, nearly one hundred, with the following result: A. Variety septenarius. Three with seven, eleven with eight ribs. B. Variety Jeffersonius s.s. Eighteen with nine, twenty-eight with ten, thirteen with eleven ribs. FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA NI NO ios) C. Variety edgecombensis. Seven with twelve, one with thirteen, five with fourteen, two with fifteen, two with sixteen, one with seventeen, and one with twenty ribs. The typical number for the species, therefore, would seem to be nine or ten primary ribs. The surface is covered with fine radial threads, and in this species they are very close together, even in size, closely set with small raised scales. The fact that these scales are so close to one another makes the transverse lines pretty even. In Madisonius the threads are larger, the scales larger and more sparsely distributed on the threads, so that they frequently have an alternated aspect. The threads are usually very uniform in size in /effersonzus, but it fre- quently happens in the specimens with more numerous primary ribs that the middle threads in the interspaces will be somewhat larger than the others. This is not very apparent in the specimens which retain the scales perfect, but in those which are worn the interspaces seem to have a distinct mesial thread. It was to this kind of mutation that Conrad gave the name of edgecombensis, the type-specimens of which are in the National Museum. When there are fewer primary ribs, as in the type of the species or the variety septenarvius, the threads are more uniform over the wider ribs and inter- spaces. The most conspicuous character by which the peripheral specimens of Jeffersonius can be discriminated from those of A/adisonzus is comprised in the sculpture and form of the byssal ear. In /effersonius it is sculptured with fine, uniform, numerous threads, and the notch is shallow and leaves an incon- spicuous fasciole. In Madzsonius the upper part of the ear is provided with comparatively few and coarse threads, and the notch is wide and deep, with a broad and well-marked fasciole. Counting the ribs of seventy adult speci- mens of Madisonius in the collection, the following result was obtained : A. Variety Wadisonius s.s. Four with twelve, five with thirteen, eight with fourteen, twenty-three with fifteen, fifteen with sixteen, nine with seven- teen, and two with eighteen ribs. B. Variety Sayanus. One with thirteen and four with fifteen ribs. It would seem, therefore, that the normal number of ribs in Madzsonius is fourteen to seventeen. The two species usually, but not invariably, differ in convexity, /e/fer- II TRANSACTIONS OF WAGNER 9 Tet TERTIARY FAUNA OF FLORIDA sonius being the more inflated. The two valves are usually nearly equal in this respect. As there are more ribs in AJadzsonius, they are necessarily narrower, and as the threads are coarser, there are fewer of them on top of the ribs. From this it results that the ribs, as noted by Say, often bear three scabrous threads, sometimes five, young specimens occasionally only two, and similarly in the interspaces, whereas on the backs of the ribs the mesial thread is often more prominent than the others. The three-threaded form was called éricarinatus by Conrad, though it appears to have been the original type of Say. The young two-threaded form at first appears very distinct, but such shells ac- quired the third thread with growth. Rarely in this species the threads are fine and uniform, as in /effersonius, but the byssal ear will enable the specimen to be rightly identified. On the whole, it seems as if in Southern specimens the tendency of /Jeffersonius was to be flatter and have more ribs, and in the Maryland and Virginia form to have fewer ribs and more convex shells. Still, the variety sep/enarius is reported from South Carolina, and a larger series of specimens from Southern localities might show this generalization does not hold uniformly. The young shells of this group would be naturally placed in the section Ch/amys, and the peripheral species in time, such as those of the Eocene and Pliocene, though obviously related to the Miocene type, are perhaps best placed there also. Except in the absence of nodes they are equally close to Nodipecten. Even in the Miocene we have species which are strictly intermediate between lacopecten, Lyropecten, and Chlamys s. s. Hence, no one who carefully studies the various types can feel that a multiplication of genera faithfully represents the facts of nature. Pecten (Lyropecten) Madisonius Say. Fecten Madisonius Say, Journ. Acad. Nat. Sci., 1st Ser., iv., p. 134, 1824; Conrad, Fos. Medial Tert., p. 48, pl. 24, fig. 1, 1840. Pecten tricarinatus Conrad, Am. Journ. Conch., iii., p. 189, 1867. Fecten fraternus Conrad, Proc. Acad. Nat. Sci. Phila. for 1862, pp. 291, 581, 1863. Miocene of New Jersey at Shiloh and Jericho, Cumberland County ; of Maryland at St. Mary’s River, Greensboro’, Choptank River, Langley’s Bluff, near Skipton, Barker’s Landing, Plum Point, and Calvert Cliffs; of Virginia at Coggins Point, Temple Place on the York River, Jones’s Wharf and Grove Wharf, Suffolk, and Petersburg, and of North Carolina at Snow Hill, FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA NI to On Pecten Madisonius var. Sayanus. n. var. PLATE 26, FIGURE 6. Upper Oligocene (Alum Bluff beds) of Oak Grove, Santa Rosa County, Florida; on the Chattahoochee River at Old Chattahoochee Landing, at Rock Bluff, and on the Chipola River in the Chipola beds. This form is the percursor in the Upper Oligocene of the typical A/adz- sonius of the Miocene. It differs from the latter in its extreme compression, the ribs, except in the umbonal region, being almost obsolete. Alt. 120, lat. 135, diam. about 16 mm. This is what has been referred to /Jeffersonius and Madisonius by L. C. Johnson, Foerste, and other observers in the Floridian Oligocene. The characteristics of P. Madisonius have been pointed out under P. JSeffersonius, from which it differs by its more compressed shell, more numerous ribs, and coarser and more scabrous sculpture, as well as the deeper and wider byssal notch. The young rarely have the scales continuous across the tops of the ribs. Pecten (Lyropecten) sp. indet. a. Lower Oligocene at Sulphur Springs ferry, Suwanee River, Suwanee County, Florida (Vicksburg horizon ?). Shell small, thin, flattish, with eleven strong, rounded ribs, separated by slightly wider interspaces ; submargins narrow, radially striated; surface prob- ably with concentric elevated and faint radial sculpture when perfect. Alt. 30, lat. 37, diam. about 7 mm. I have noted this species, as nothing like it has been described from the Vicksburgian, and it has every appearance of being a precursor of the Miocene Lyropectens. The fossil is a silicified pseudomorph, with the surface worn and the ears defective. It is possible that the bed from which it came is the upper Ocala or Nummulitic part of the Vicksburgian, though the rock shows no Nummulites. ay Several closely allied species on the border line between the sections, and which, except for their more delicate shells and smaller size, might equally well be placed with the Lyropectens, will be found under the head of Mod- pecten, Chlamys, and Placopecten. g Pecten (Placopecten) Clintonius Say. Pecten Clintonius Say, Journ. Acad. Nat. Sci. Phila., 1st Ser., iv., p. 135, pl. ix., fig. 2, 1824. Pecten magellanicus Conrad, Journ, Acad. Nat. Sci, Phila., 1st Ser., vii., p. 153; not of Gmelin, 1792. TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA NI to (oy Pecten principotdes Emmons, Geol. N. Car., p. 280, fig. 198, 1858. Pecten clintonensis Meek, S. 1. Checkl. Mioc. Fos., p. 5, 1864. Chlamys (Placopecten) Clintonius Verrill, Trans. Conn. Acad., x., p. 78, 1897, in part. Pecten princeps Vernill, of. cit., in syn., non Emmons. Pecten Muller? Vervill, op. cit., in syn., not of Dall. Miocene of Coggins Point, Grove Wharf, York River, and James River, Virginia, Rogers, Conrad, Lea, and Harris; and of Maryland, Dr. Foreman ; and of North Carolina at Murfreesboro, Meherrin River, Emmons. This remarkable shell appears to be quite limited in its range, and is only known in the Miocene of Maryland, Virginia, and North Carolina. It presents at a first glance a remarkable resemblance to the recent Pecten magellanicus (Ch.) Gmelin, which is doubtless its descendant. The latter can, however, be at once discriminated from the fossil by the shorter hinge-line, higher auricles, much narrower resiliary pit, and, usually, the smaller and less central adductor scar of the recent shell. A very large series of both recent and fossil speci- mens which I have carefully studied confirms the uniformity of the above- mentioned characters. As a rule the radiating threads in the fossil are markedly coarser than those of the living species. In both the byssal notch of the adult is represented by a shallow sinuation, and the ctenolium, present in the immature stages, is usually buried in shelly matter in the adult. Since so much confusion has occurred between these two species, a state- ment of the synonymy of the living form may be useful. Pecten (Placopecten) magellanicus Gmelin. Amusium magnum magellanicum, etc., Chemnitz, Conchyl. Cab., vii., p. 290, pl. 62, fig. 597, 1784; Schroter, Einl. Conch., iii., p. 323, 1786; Favanne, pl. 55, fig. e, 2. Ostrea magellanica Gmelin, Syst. Nat., vi., p. 3317, 1792 (not 1788, as frequently quoted) ; Dillwyn, Descr. Cat. Rec. Sh., i., p. 250, 1817. Ostrea grandis Solander, Portland Cat., 1786 (fide Humphrey). Pecten grandis Humphrey, Mus. Cal., p. 51, No. 969, 1797. ? Amusium testudinarium Bolten, Mus. Bolt., p. 165 (name only), 1798 ; 2" Ausg., p. 115, 181g. j Pecten magellanicus Lam., An. s. Vert., vi., p. 165, 1819; ed. Desh., vii., p. 134, 1834 ; Gould, Inv. Mass., p. 132, 1842; ed. Binney, p. 196, fig. 494, 1870; Conr., Am. Mar. Conch., i., p. 6, pl. i., fig. 1, 1831 ; Stm., Sh. N. Engl., p. 8, 1851. Pecten fuscus Linsley, Am. Journ. Sci., 1st Ser., xlviii., p. 278, 1845 (name only); Gould, Am. Journ. Sci., 2d Ser., vi., p. 235, fig. 6, 1848; Stm., Sh. N. Engl., p. 8, 1851. (Young shell.) Pecten brunneus, Stm., Sh. N. Engl., p. 58, in errata, 1851. (Young.) FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA a i iS) SY Pecten tenuicostatus Mighels and Adams, Proc. Bost. Soc. N. Hist., i., p. 49, 1841 ; Bost. Journ. Nat. Hist., iv., p. 41, pl. 4, fig. 7, 1842. (Young.) Pecten tenuicostatus Verrill, Rep. U.S. Fish. Com., 1871-2, pp. 509, 696, 1873. (Adult.) Chlamys (Placopecten) Clintonius Vervill (ex parte), Trans. Conn. Acad. Sci., x., pp. 69, 78, pl. xvii., figs. 1-7; pl. xx., figs. 7, 8, 8a; pl. xxi., figs. 1, 1a, 2, 2a, 1897. Pecten (Pseudamusium) Mullert Verrill, op. cit., p. 78, not of Dall. Pecten (Pseudamustum) striatus Dall, Bull. U. S. Nat. Mus., No. 37, p. 34, No. 40, 1889 (not of Miiller, 7d@e Verrill), young shell ; Verrill, of. czz., p. 96, in errata, 1897. Pleistocene of St. John, New Brunswick, and Gardiner’s Island, New York; living from Labrador southward, in increasing depths of water, to Cape Hatteras, North Carolina. The sculpture of the more northern specimens is less strong than in those from more southern habitat, and for the former Professor Verrill suggests the retention of Mighels’s name ¢ezzicostatus (originally given to the young shell) in a varietal sense. This is not P. cenwicostatus Hupé, in Gay’s Chile, 1854. As previously noted, the writer sees no reason why Gmelin’s name, given in error as to the true habitat of this species, but universally familiar, should not continue to be used. If, however, an exaggerated purism demands a change the next most appropriate name is that of Solander, given without description in the Portland Catalogue, described in the Banksian MSS., and cited by Humphrey as the Great Compass shell from Newfoundland, with nearly equal valves, remarks which cannot possibly apply to any other species. He not unnaturally places it after the species of Avuzsium, as H. and A. Adams did in their Genera of Recent Mollusca (ii., p. 55) sixty years later. Pecten (Placopecten) virginianus Conrad. Pecten virginianus Conr., Fos. Medial Tert., p. 46, pl. xxi., fig. 10, 1840. Miocene of City Point, Virginia; E. Ruffin. This is a puzzling shell, of which only the type specimen (a right valve) and one other valve are known. It appears like a young shell of P. Cintonius in all essentials, except that it is more convex and has the byssal ear separated by a broad fasciole and deep notch from the submargin and is provided with a strong and conspicuous ctenolium. The young shells of P. Clintons of the same size (altitude fifty-eight millimetres) as the type of wgzanus have not these characters, as an examination of a large number has shown. A speci- men of the same valve from Coggins Point, Virginia, identified by Conrad as virgimianus, seems to me merely a young P. Chintonius with a somewhat deeper notch than usual, but the original type specimen differs more markedly, and TRANSACTIONS OF WAGNER 728 TERTIARY FAUNA OF FLORIDA until intermediate speciniens are obtained I should not feel justified in sup- pressing the species. Pecten (Placopecten ?) marylandicus Wagner. Pecten marylandicus Wagner, Journ. Acad Nat. Sci. Phila., viii., p. 51, pl. 2, fig. 1, 1838. Pecten tenuis H. C. Lea, Trans. Am. Phil. Soc., 2d Ser., ix., p. 246, pl. 35, fig. 33, 1845. Miocene of the Patuxent River, at Jones’s Wharf, Maryland, Wagner; of Petersburg, Virginia, Lea; and the Meherrin River, North Carolina. I have examined the types of P. marylandicus in the Academy’s collec- tion, and the type of Lea’s species is in the collection of the National Museum. It is difficult to say to which section the species should be referred, as in the typical P. marylandicus the radiating threads often are gathered into fasci- cles (fifteen to seventeen) which crenulate the valve margin, while in P. ¢enads the threads are not fasciculated and the margin is entire. In the former the interior is fluted, in harmony with the external sculpture, while in the type of tenuis the fluting is quite obsolete, though there are faint radial striations near the margin. In sarylandicus the radial sculpture averages coarser than in tenuis. Yet these differences march closely with those observed in a large series of P. hericeus Gould from the northwest coast, and the other characters are so similar that I feel indisposed to assign specific rank to the differences. In the largest and finest specimens of P. marylandicus there are fluctuated scales concentrically arranged on each side of a mesial thread, in the inter- spaces between the principal ribs. The shell attains an altitude of ninety anda width of ninety-five millimetres, and the byssal notch is deep and conspicuous. The species forms a transitional link between Placopecten and Chlamys s. s. Pecten (Nodipecten) nodosus Linné. Ostrea nodosa L., Syst. Nat., Ed. x., p. 697, No. 164, 1758; Ed. xii., p. 1145, 1767. ecten corallinus Chemn., Conch. Cab., vii., p. 306, pl. 64, figs. 609-11, 1784. Pecten nodosus Lam., An. s. Vert., vi., p. 170, 1819; d’Orb., Moll. Cuba, ii., p. 353, 1845. Pecten pernodosus Heilprin, Trans. Wagner Inst., i., p. 131, pl. 164, figs. 69, 69 a, 1887. Pecten nodosus Heilprin, of. czz., p. 100, 1887. Pecten fragosus Conr., Journ. Acad. Nat. Sci. Phila., 2d Ser., 1, p. 214, pl. 39, fig. 11, 1849. Pecten magnificus Gabb, Geol. St. Dom., p. 256, 1873; not of Sowerby, P. Z. S., 1835, p- 109. Lyropecten nodosus Verrill, Trans. Conn. Acad., x., p. 91, 1897. Pliocene of the Caloosahatchie marls, Florida, Willcox; Pleistocene of FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA “MI iS) Ne) the Antilles and the north coast of South America; living in the Gulf of Mexico and the Antilles, and probably also (as P. swbnodosus) on the Pacific shores of middle America. (Cf. remarks under Lyropecten and P. subnodosus Sby., pp. 701, 710.) This species is the type of the section Modipecten. It varies in the number of ribs (seven to ten) and extremely in its amount of nodulation. Some specimens have merely turgid undulations of the ribs, as in the form first described of the Pacific swbnodosws. Others bear subglobular bull on the ribs at short intervals. Others begin without nodes and after half their growth is accomplished suddenly become nodulous. . swbnodosus varies in the same way. The deeper the water, apparently, in which the individual lives, the thinner and more nodose the shell. Mr. Willcox found some remarkably fine specimens in the marls of the Caloosahatchie. Pecten (Nodipecten ?) peedeénsis Tuomey and Holmes. Pecten peedeénsis T. and H., Pleioc. Fos. S. Car., p. 30, pl. 12, figs. 1-5, 1855. Miocene of the Peedee River, Darlington District, South Carolina, and of Virginia. This fine species frequently has the younger part of the shell nodose and the distal portions of the ribs wider, feebler, and less nodose. It has eight or nine ribs and conspicuous concentric lamellation. It seems nearly inter- mediate between the Lyropecten and Nodipecten types, and may belong to the section Macrochlamis Sacco (Bull. Mus. Zool. Torino, xii., No. 298, p. 101, June, 1897, type P. /atissimus Brocchi). Pecten (Nodipecten) condylomatus n. s. PLATE 34, FIGURES 14, 15. Oligocene of White Beach, Osprey, Florida, and of the Chipola River at Bailey’s Ferry, Florida, Burns and Dall; lower bed at Hawkinsville, Georgia, Burns. Shell small for the group, subequilateral, slightly inequivalve, the right valve more convex with nine to thirteen strong, undulated, rounded, more or less nodulous, finely radially striated ribs, the undulations affecting the whole of the disk, sudden and very pronounced, giving a side view of the valve somewhat the aspect of a clenched fist; interspaces narrower radially, finely threaded, the whole valve with fine concentric lamellation somewhat prickly or limose at the intersections; submargins rather wide, radially finely TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA NI ios) (e) striate; ears small, subequal, the surface coarsely radially threaded, the byssal ear produced with a conspicuous sinus and fasciole; ctenolium well marked ; inner basal margin fluted by the ribs; cardinal margin with two or three strong crural ridges. Alt. 40, lat. 45, diam. about 22 mm. This is an interesting species, peculiar from its small size and the abrupt- ness of its knuckle-like undulations. Some specimens, however, are but little undulated, arid the mutations are much the same as occur in other species of the section. The following species, while they are related by sculpture, form, and con- chological character to the Wodipecten type, are not known to form nodules; the ribs may be slightly tumid at intervals or periodically undulated, but there are no hollow bullz, as in the more typical forms. But these characters are precisely those of the non-nodulous varieties of the nodulous species, and so I feel justified in including them in this section. Pecten (Nodipecten) anatipes Morton. ecten anatipes Morton, Am. Journ. Sci., xxiii., p. 293, pl. 5, fig. 4, 1833; Syn. Org. Rem., p- 58, 1834. Oligocene of Mississippi, Vicksburgian horizon, at Heidelberg and in Jasper County; Johnson. The shell is small, with five or six ribs and narrower feebly striated inter- spaces; cardinal crura well developed. Pecten (Nodipecten) pulchricosta Meyer and Aldrich. Pecten pulchricosta M. and A., Journ. Cin. Soc. N. H., ix., p. 45, pl. 2, figs. 23, 23 a, 1886. Jacksonian Eocene of Wahtubbee Hills, Clarke County, Mississippi; Aldrich and Burns. Shell small, thin, with eight large ribs, which near the umbo are divided by one or two well-marked sulci, which soon become obsolete, after which the ribs are simple; the surface sculpture is of even, uniform, crowded, concentric elevated lines. The ears are subequal, the byssal notch well marked. Neither in Meyer’s figure nor in the specimens do I find the ribs dividing near the basal margin, as stated in his diagnosis. Pecten (Nodipecten) Rogersi Conrad. Pecten Rogersi Conrad, Journ. Acad. Nat. Sci., 1st Ser., vii., p. 151, 1834; Medial Tert., p. 45, pl. 21, fig. 9, 1840. FREE INSTITUTE, OF SCIENCE TERTIARY FAUNA OF FLORIDA NI On = Miocene of the James River, near Smithfield, Virginia, and of Maryland, near Skipton; Conrad and Harris. Shell with four large and two smaller lateral simple ribs, internally lirate ; submargins narrow, minutely scabrous, not radiated; the rest of the disk entirely covered with fine, squared, elevated, minutely scaly radial threads; ears subequal, finely radiated; sinus well-marked; ctenolium and cardinal crura developed. Alt. of type 20, lat. 1g mm. This is not the Pecten (Pseudamusium ?) Rogersi Clark, Bull. U. S. Geol. Surv., No. 141, p. 85, pl. 34, figs. 2 a—-d, 1896, from the Eocene of Potomac Creek, Front Royal, Virginia. For the latter the specific name of frontalts is suggested, since there is already a species named for Professor Clark. Pecten (Nodipecten) caloosaénsis n. s. PLATE 29, FIGURE 12. Caloosahatchie Pliocene marl of the Caloosahatchie River and Shell Creek; Willcox and Dall. Shell moderately large, with four principal ribs and sometimes a sub- sidiary, much smaller, rib at the inner edge of the submargins; backs of the ribs strongly radially striated or even threaded, the interspaces smooth or with only obsolete traces of striation, equal to or wider than the ribs; concentric sculpture usually weak, of close-set concentric elevated or incremental lines ; submargins wide, the outer margins smooth, the inner threaded like the backs of the ribs; ears large, triangular, widest at the cardinal margin and pointed at the distal cardinal angle, their sculpture radial, not crowded; feeble, except upon the byssal ear, where the threads are strong and concentrically scabrous ; byssal notch wide, shallow, the fasciole conspicuous; ctenolium distinct; in- terior reflecting the external ribs; hinge with the crura present but feeble in the young; the old specimens have them obsolete, but on the cardinal margin a relatively broad ligamentary area is formed. Alt. 83, lat. 80, diam. 30 mm. This is one of the finest and most characteristic species of the Pliocene, remarkable for its wide, acute ears, and for having the interspaces of the ribs nearly smooth, although the ribs are striated. Pecten (Nodipecten) antillarum Recluz. Pecten antillarum Recluz, Journ. de Conchyl., iv., p. 153, pl. 5, fig. 1, 1853 (May) ; Beau, Cat. Coq. Guadelupe, p. 21 ; Arango, Fauna Mal. Cubana, ii., p. 209, 1878. Pecten fucatus Reeve, Conch. Icon., Pecten, pl. xxxi., fig. 139 a-b, 1853 (June); Krebs, W. I. Mar. Shells, p. 134, 1864. TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA Pecten (Pseudamussium) argenteus Marrat, Argo Exped., p. 7, 1876; not of Reeve. (An immature specimen.) Pecten sulcatus Krebs, W. 1. Mar. Shells, p. 134; not of Lam. Pliocene and Pleistocene of the Antillean region; living in Cuba, Guade- lupe, the Bahamas, and the Florida Keys. This species is often destitute of the nodosities, and in that condition is referable to Chlamys. The very young shell is thin and glistening, in which ‘state it has been mistaken for the Chinese P. argenteus Reeve. Old and worn specimens have been taken for P. sadcatus Lam. Its analogue and precursor in the Antillean Oligocene is the P. anguillensis Guppy. Pecten (A%quipecten) perplanus Morton. Pecten sp. Lesueur, Walnut Hills Fos., pl. 5, fig. 2, 1829. Pecten perplanus Morton, Am. Journ. Sci., xxili., p. 293, 1833; Org. Rem., p. 58, pl. 5, fig. 5, and pl. 15, fig. 8, 1834. Z Pecten Spillmani Gabb, Journ. Acad. Nat. Sci., 2d Ser., iv., p. 402, pl. 68, fig. 3, 1860. Eocene of St. Stephen’s, Alabama, Morton; of the Jacksonian at Jack- son, at. Turk’s Cave, Cocoa Post-Office, Choctaw County, and Fair Post-Office, near Claiborne, Alabama; at Pachula Creek and Shubuta, Clarke County, Mississippi; in the Vickburgian or Lower Oligocene, near Gainesville, Alachua County, at-various localities in Levy County, and in the Nummulitic horizon at Ocala, Florida, Dall, Burns, and Johnson; Grant Parish, Louisiana, Johnson. Shell with twenty-three to twenty-five subangular ribs with sloping sides and equally wide shallow interspaces, an obsolete thread on each side of the median keel of each rib, stronger on the side away from the middle of the valve ; in large ones another thread begins near the basal margin; whole shell covered by regularly spaced low, thin concentric lamellz, not crowded, which are slightly produced as a little linguiform process over each rib and thread, more prominent on the right valve, which has rather small, short ears, with three to five spinose or imbricate radii, and a conspicuous but not deep byssal notch; left valve with sharper keels, feebler concentric lamella, subequal ears, with five or six low beaded radii; shell plump in both valves, internal margin strongly fluted; hinge with the cardinal crura strongly developed and cross- striated. Alt. 34, lat. 35 mm. A full description is given, as I have found this shell much confused in nearly all the collections with P. Poulson, P. nuperus, and others. The types of P. perplanus and P. Spillmant have been compared and their identity fully FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA SI ios) Ow confirmed. P. nuperius belongs to the section Ch/amys and, though with very similar sculpture, is a more elevated and less rotund species. Worn speci- mens of perplanus which have lost the scaly sculpture have a very different aspect and are often puzzling. A variety has the threads with minute crowded scales, while the tops of the ribs are smooth, giving them a laterally fringed appearance; these specimens have twenty-two ribs only. This form was obtained at the Natural Bridge, Alachua County, Florida, and in the lower bed (Hawthorne horizon) at Hawkinsville, Georgia, by Burns. Pecten (perplanus var. ?) centrotus Dall. PLATE 34, FIGURE 21. Eocene (Vicksburgian ?) of the Ponce de Leon artesian well, St. Augus- tine, Florida, at a depth of two hundred and twenty-five feet; Willcox. Shell like the preceding, with twenty-three flat-topped smooth ribs with lateral fringes which wholly fill the interspaces but do not unite in the middle of the channel. Two or three of the ribs near the middle of the disk show six to eight distant, regularly spaced short spines projecting from their tops ; the other ribs are destitute of spines. Interior sharply and deeply grooved to correspond with the external ribs. Alt. 20, lat. 18.5 mm. The single valve obtained is somewhat defective, but its sculpture is so different from any of the other forms that it seemed best to describe it. Pecten (AWquipecten?) choctavensis Aldrich. Pecten choctavensts Aldrich, Harr. Bull. Pal., ii., p. 68, pl. 5, fig..7, 1895. Eocene of Wood's Bluff, Choctaw County, Alabama; Aldrich. This shell when not worn has a very flat imbricated sculpture over all, pointed on the backs of ribs and riblets, the surface on the interspaces being quincuncially microscopically punctate. It is rather flat for an Aguzpecten, and is one of the many peripheral species uniting the different sections. Pecten (Atquipecten) chipolanus n. s. PLATE 29, FIGURE 9. Upper Oligocene of the Chipola marls, lower bed at Alum Bluff, and the silex beds at Ballast Point, Tampa Bay, Florida; Dall and Burns. Shell solid, rounded, plump, with fifteen to seventeen strong, rounded ribs with narrower interspaces which are almost channelled, both ribs and chan- nels with continuous fluctuated, sometimes crowded, low concentric lamelle ; TRANSACTIONS OF WAGNER a9 734 TERTIARY FAUNA OF FLORIDA the ribs faintly grooved distally on top; the concentric sculpture sometimes strong on three or more ribs and almost absent on the intervening ones; hinge-line wide, ears large, with conspicuous but not deep notch, with six or seven coarsely imbricated, close-set radial threads on the byssal ear and more numerous threads on the others; submargins nearly smooth; cardinal crura strong; inner basal margin with strong, short flutings, obsolete above. Alt. 25, lat. 25, length of hinge-line 18 mm. Pecten (Aiquipecten) suwaneénsis n. s. Vicksburgian of Suwanee County, Florida; Johnson. Shell with twenty-two entire, rounded ribs, with narrower, rather shallow interspaces crossed by little raised, concentric, not crowded, more or less fluc- tuated laminze continuous over ribs and spaces, with lateral grooves on the ribs near the basal margin; submargins narrow, smooth; ears subequal, moderate, with fine, close, concentric sculpture and four or five distant fine imbricated radii; notch distinct, rather deep. Alt. 20, lat. 20 mm. This form differs from P. Anesskernt by its unchannelled interspaces, con- tinuous concentric lamella, and subequal ears; from P. chzpolanus by feebler and more numerous ribs, shorter ears, and less conspicuous sculpture. It is flatter, thinner, and smaller than the weakest specimens of P. perplanus, and while its characters are not marked, does not seem to be unitable with any of the others of its section. PP. uperus, which is the nearest to it among the species of C//damys, has a more solid shell, more sharply keeled ribs, and differently sculptured ears, while its form is decidedly more ovoid. Pecten (Atquipecten) glyptus Verrill. Pecten glyptus Vervill, Trans. Conn. Acad., v., p. 580, 1882; Dall, Proc. U.S. Nat. Mus., xii., p. 248, pl. 8, figs. 2 and 3, 1889. Pecten Tryont Dall, Bull. Mus. Comp. Zool., xvili., p. 438, 1887. Chlamys (dEquipecten) glypta Vervill, Trans. Conn. Acad., x., p. 76, 1897 ; in part. This species is cited here as the only true living representative on our coast of the section gmpecten, and it is rather more inequilateral than typical species of that group. It has been found from the vicinity of Cape Hatteras to the continental bench off Martha’s Vineyard. Professor Verrill’s specimens were very imperfect, and some worn fragments of another species, P. phrygium Dall, were confused with those belonging to P. glyptus in Pro- fessor Verrill’s cited paper. Of his figures on plate xvi. 7, 10, and per- FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA ™N ios) on haps 11 represent badly worn P. phrygium, while figs. 8 and 9 are taken from the worn type of P. glyptws. Perfect specimens of the latter are in the National Museum and were figured as above cited in its Proceedings. It is not yet known in the fossil state. Pecten (Chlamys) islandicus Miller. Pecten islandicus Miller, Prodr. Zool. Dan., p. 248, 1776. Ostrea cinnabarina Born, Test. Mus. Vind., p. 103, 1780. Pecten rubidus Martyn, Univ. Conch., No. 153, pl. 53, fig. 1, 1784. Ostrea demissa Solander, Mus. Calonn., p. 52, 1797. Pecten Pealeti Conr., Am. Mar. Conch., 1, p. 12, pl. 2, fig. 2, 1831. Pecten Fabrictt Phil., Abb. und Beschr., iv., p. 3, pl. 1, fig. 5, 1844. Chlamys costellata Verr. and Bush, Trans. Conn. Acad., x., p. 75, 1897. (Very young shell.) Pleistocene of New England and New Brunswick and northward in the bowlder clays, also on the North Pacific coasts in deposits of the same age; living from the Arctic waters southward to Chesapeake Bay. The minute shell described by Professor Verrill under the name of cos- tellata is \ess than five millimetres long and has not assumed the adult char- acteristics. From an examination of the type I see no reason to doubt that it is a very young specimen of the present species. This shell is the type of the subgenus Chlamys. Pecten (Chlamys) Kneiskerni Conrad. Pecten Knetskernt Conr., Am. Journ. Conch., v., p. 40, pl. 1, fig. 18, 1869. Pecten Knetskerni Whitfield, Lam., N. J., p. 224, pl. 29, fig. 5, 1885 ; in part. Eocene marl of Shark River, New Jersey, Conrad; Jacksonian Eocene of Claiborne, Alabama, and Enterprise, Mississippi, Johnson; Oligocene of the Chipola beds, Monroe County, Florida (?), Burns. In Professor Whitfield’s attempt to identify the cast of an immature shell named as above by Conrad, the former has evidently brought together the young, uncharacteristic shells of several species of Ch/amys. Conrad’s shell was described as having thirteen ribs and none on the submargins ; Whitfield gives the species fifteen to fifty ribs and radiated submargins. This is a range altogether too great for a single species. Probably some of Professor Whit- field’s specimens were young choctavensis, which has an unusually large number of ribs. I have supposed a shell from the Jacksonian might represent the unidentifiable species of Conrad. This has twenty-five ribs, divaricating TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA NI [oS) (=) near the base with rather sparse concentric imbrications; ribs wider than the interspaces, entire in the young; valves rounded; ears rather small with concentric imbricated radii and rather deep byssal sulcus. Another form, which apparently has not yet taken on its adult character- istics, has been described from the same beds by Whitfield under the name of P. Rigbyt. Wt is said to have from twenty-two to twenty-six ribs with strong, close concentric scales. It differs from Aneskernt, according to Whitfield, by its wider and stronger ribs with closer and more prominent imbrication. (Whitfield, of. czz., p. 226, pl. 29, fig. 6, 1885.) Pecten (Chlamys) membranosus Morton. Pecten membranosus Morton, Org. Rem., p. 59, pl. 10, fig. 4, 1834. Pecten carolinensis Conr., Kerr, Rep. Geol. N. Car., App., p. 18, pl. 3, fig. 2, 1875 ; not Lyropecten carolinensis Conr., 1875. Eocene of Jones County, Haldeman; of Rocky Point and Wilmington, North Carolina, Stanton; Eutaw Springs, South Carolina, Conrad. This somewhat resembles the recent P. orvatus Lam., but is shorter and more orbicular. There is no question of the identity of Mr. Conrad’s P. carolinensis with Morton’s species; I have compared the types. Pecten (Chlamys) wahtubbeanus n. s. PLATE 34, FIGURE 9. Claibornian and Jacksonian Eocene of Louisiana, Alabama, and Mis- sissippi; abundant at Wahtubbee; Burns. Shell small, flattish, with small, unequal ears and rounded disk; fourteen or fifteen ribs carrying basally three densely finely imbricated, rounded threads, the interspaces narrower with two crenulate threads; submargins with close, fine, imbricate threads; ears prominent, with a deep, wide byssal notch, radi- ately imbricate with coarse, elevated radial threads ; interior with shallow sulci, the cardinal crura developed but no lire on the disk. Alt. 22, lat. 22 mm. This species differs from the Claibornian P. Deshayesa Lea by its threaded and less individualized ribs, its similarly sculptured valves, more conspicuous notch, and concentric sculpture and smaller size when adult. FP. Johnsoni Clark, from the Maryland Eocene, has more numerous ribs with simpler sculpture, and which increase by intercalation instead of dichotomy. A shell which I suppose to be the same as Clark’s was obtained from the Jacksonian of Clarke County, Mississippi, by Johnson, FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA MN ios) NI Pecten Johnsoni Clark (Bull. U. S. Geol. Surv., No. 141, p. 85, fig. 3 a, 3.4, 1896), from the Eocene of Maryland, is a young shell, not fully exhibiting the adult characters, and of which the type specimen seems worn. It belongs in this vicinity, but has twenty ribs, with single short intercalary threads, crossed only by fine lines of growth. The specimens were obtained from Potomac Creek, Va. Pecten (wahtubbeanus var. ?) Willcoxii n. s. PLATE 29, FIGURE 4. Eocene of Clarke County, Mississippi, and of the Wahtubbee hills (Claibornian); Johnson and Burns. Shell small, broad, flattish, thin; left valve with about sixteen narrow, rounded, elevated ribs, with somewhat sparse, regularly spaced prickles on their tops; between the ribs are similar, but lower and smaller, non-dichoto- mous radial threads; submargins very narrow, nearly plain, with faint Camp- tonectes striation; ears small, subequal, except the byssal ear, which is longer, narrow, with a deep sinus and conspicuous fasciole, and about six scabrous radii, the right posterior ear with concentric striz and only faint traces of a few radii; the ears on the left valve similar, with five or six strong scabrous threads; internal basal margin of left valve with short flutings in harmony with the radial sculpture ; the disk not grooved; in the right valve the internal channels are more pronounced; the right hinge-line has a single crural ridge parallel with the margin on each side of the pit. Alt. 23, lat. 24 mm. This form is closely related to P. wahtubbeanus, from which it differs by the isolated character of the prickles on the ribs, which are replaced in zwah- tubbeanus by more or less continuous concentric lamellation, while the ribs of the right valve of the latter are more or less split up, but in P. Willcoxii present the appearance of a fascicle of separate threads. In worn specimens of wahtubbeanus the ribs appear rounded and plain after the removal of the scales ; in Willcox the division into threads is distinct. Nevertheless it is possible that a larger series may show the two forms to be merely the ex- tremes of a single species. From P. membranosus the present form is easily distinguished by wider hinge-line, larger ears, thinner shell, and by its radial threads fasciculated rather than subequally level. It is named in honor of Mr. Joseph Willcox, to whom our Tertiary Paleontology is so much indebted. Pecten (Chlamys) Deshayesii Lea, Pecten Deshayesii Lea, Contr. Geol., p. 87, pl. 3, fig. 66, 1833. Fecten Lyell Lea, op. cit., p. 88, pl. 3, fig. 67. (Young.) TRANSACTIONS OF WAGNER 738 TERTIARY FAUNA OF FLORIDA Pecten Deshayestt var. tirmus Gregorio, Claib. Mon., p. 181, pl. 21, fig. 15, 1890. ? Pecten minutus Lea, op. cit., p. 88, 1833. Not P. Deshayesit Nyst, Coq. et Polyp. Fos., p. 288, 1845. Jacksonian of St. Stephen’s Bluff, Tombigbee River, Alabama, of Clai- borne, Mississippi, and four miles west of Live Oak, Florida; Burns and Stanton. This species is positively known to occur in the Jacksonian at Claiborne and elsewhere, but I have obtained no specimens from the vast amount of marl belonging to the true Claibornian sands horizon which has come under my notice. The shell is rather variable, losing the concentric sculpture when worn. It has fifteen to twenty-one ribs; the byssal notch is inconspicuous; in the right valve the ribs are strong and rounded on top with the concentric sculp- ture chiefly evident at their sides, the interspaces sparsely imbricated with one or two interstitial divaricate threads near the base; ears flattish, slightly scaly, with radial grooves, notch very shallow; left valve with the sculpture like that of P. wahtubbeanus but much less dense. Altitude and latitude forty- eight millimetres. There is hardly any room for doubt that Lea’s other species are merely the immature stages of this same shell. Pecten (Chlamys) cocoanus n. s. PLATE 34, FIGURE 23- Jacksonian Eocene of Red Bluff, Mississippi, and Cocoa Post-Office, Choctaw County, Alabama; Burns. Shell small, thin, flattish, oblique, produced behind, with about twenty- five small, low, entire ribs, rounded above, and about fourteen interstitial single smaller threads, the tops of all of which are somewhat sparsely concentrically imbricated, the interspaces showing only incremental lines ; ears quite unequal, small, the posterior smaller, each with five or six low, hardly scaly radii; inside of the valve obsoletely channelled, the cardinal crura developed. Alt. 23, lat. 23 mm. This shell differs from P. membranosus by its entire and less numerous ribs, and from P. wahtubbeanus by its greater obliquity, its entire, less con- spicuous, and less densely imbricated ribs. Pecten (Chlamys) Greggi Harris. Pecten Gregg? Harris, Bull. Pal., ix., p. 45, pl. vil., figs. 4-5, 1897. FREE INSTITUTE OF SCIENCE 739 TERTIARY FAUNA OF FLORIDA = Lignitic or Chickasawan- Eocene at Bell’s, Greggs’s, and Peach Tree Landings, Alabama, and Fort Gaines, Georgia. This species is well distinguished by its narrow, simple, often distally obsolete ribs, usually about twenty-four in number, with wider interspaces, thin shell, small ears, and ovate form. Pecten (Chlamys) clarkeanus Aldrich. Pecten clarkeanus Aldr., Harr., Bull. Pal., 2, p. 68, pl. 5, fig. rr, 1895. Eocene of the Lisbon horizon, Sowilpa Creek, Alabama, Aldrich; and at Black Bluff Shoals, Brazos River, Texas, Lea collection. This species resembles worn specimens of P. wahtubbeanus, from which it differs by its more numerous (thirty to thirty-eight) ribs and its singular habit of intermitting the production of ribs altogether at times, so that the beak will show well-defined ribbing and a part of the disk be perfectly ribless, while later on the ribs may appear again. It should be noted, however, that only about three out of ten valves show the latter feature, the others having continuous plain ribs from beak to margin. Some of the forms included by Whitfield under P. Kueiskerni may belong here. Pecten (Chlamys) nuperus Conrad. Pecten muperus Conrad, Proc. Acad. Nat. Sci. Phila., vii., p. 259, 1854. Pecten nuperum Conrad in Wailes, Geol. Miss., p. 289, pl. xiv., fig. 11, 1854. Jacksonian Eocene of Jackson, Mississippi, Conrad and L. C. Johnson; Montgomery, Grant Parish, Louisiana, Vaughan; Russell’s Springs, Decatur County, Georgia, Pumpelly; also in the Vicksburgian at Arredondo, Florida, Johnson. This species has been very generally confounded with P. perplanus Morton, from which to a casual glance it chiefly differs by its chlamydoid form. On more careful inspection, however, it will be observed that P. zuperus has fewer ribs (czvca twenty-two), which, though somewhat similarly scabrous, are not accompanied by beaded lateral threads; the ears are higher and larger, the submargins wider, longer, and more conspicuous, and the radii of the ears are formed by rows of sparse, fluctuated, little-elevated scales, rather than by threads. The ribs of the disk in adults are keeled, with V-shaped narrower interspaces, the whole sculptured with continuous, fluctuated, con- centric, rather close-set, little-elevated, very thin lamella, which are usually worn off more or less. In the right valve, as well as in young or worn speci- 12 TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA 740 mens, the ribs are more rounded. On the whole, the species appears to be sufficiently well discriminated. The only other described Eocene species from the Atlantic coast is P. antsopleura Conrad (Kerr, Geol. N. Car., App., p. 18, 1875), the type of which is a large, heavy shell which has lost its hinge, and was collected by Dr. Yarrow ) ‘forty miles south of Beaufort, North Carolina,’ which would put its locality near New River, Onslow County. It is of ovate shape, with large, squarish ears, and very irregular, large, radial, strongly but sparsely scabrous ribs, rounded above with two or three smaller riblets on each side more depressed than the centre of the rib.. Alt. 85, lat. 70 mm. The shell is much bored by pholads and badly wormeaten and worn. It looks like a dilapidated valve of Finnites or Spondylis, and its horizon is entirely uncertain. Pecten (Chlamys) alumensis n. s. PLATE 34, FIGURES 10, II. Oligocene of the Chipola horizon, in the lower bed at Alum Bluff, Chattahoochee River, Florida; Dall. Shell small, thin, with compressed, flattish umbones and fourteen or fifteen feeble, obsolete ribs on the lower part of the disk separated by equal shallow interspaces; the whole surface marked with fine concentric lines; ears subequal, concentrically striate, not radiated, except the byssal ear, which has five scabrous riblets and a well-marked notch; interior fluted to corre- spond with the external ribs; the cardinal crura developed. Alt. reaching 15-18 mm. in fully adult shells; figured specimen 8, lat. 7.5 mm. This small shell is sufficiently distinct in its characters to indicate its specific rank, though it may be that it attains a larger size when adult than any of the specimens obtained. One or two of the specimens have the ribs more rounded and prominent than the majority. Pecten (Chlamys) tricenarius Conrad. Pecten tricenartus Conr., Proc. Acad. Nat. Sci. Phila., i., p. 306, 1843; Fos. Medial Mert spai As pleA2hatioan2 = (Miocene ?) Pamunkey River, Virginia; Tuomey. Of this species only the type is known, and the horizon is uncertain. It has somewhat of the outline of P. perplanus, but has a smaller shell and larger ears. The disk shows thirty-five rounded, nearly smooth, not dichoto- mous ribs, somewhat irregular in size, with equal interspaces, smooth and FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA 741 uniform. ~The ears are radially threaded, the byssal ear with four riblets over a rather wide and deep notch. The submargins are short and small, with traces of Camptonectes striation but no radial sculpture. The type is in the Academy’s collection. Pecten (Chlamys) decemnarius Conrad. Pecten decemnarius Conr., Journ. Acad. Nat. Sci. Phila., vii., p. 151, 1834; Fos. Med. Tert., p. 49, pl. 24, fig. 2, 1840. Pecten dispalatus Conr., Fos. Med. Tert., p. 74, pl. 42, fig. 3, 1845. Miocene of City Point, Coggins Point, and York River, Virginia, Burns and Harris; Pamunkey River, Virginia, Conrad; also in the Ashley River phosphate rock, of South Carolina, Dall. This species is notably irregular in its sculpture, the disk being sculptured either by numerous more or less distinctly fasciculated, small, radial threads, or the fasciculi may be replaced partially by stout, elevated, rounded ribs, with wide, radially threaded interspaces. The radial sculpture may be nearly smooth or covered with a conspicuous, dense, concentric lamellation. Three or four of the ribs may be more prominent than the others, and the smaller ones uneven in size and rugose, forming the variety azspalatus. When the fasciculi are rib-like they are usually dichotomous. The umbonal region in typical decemnarius is usually feebly sculptured, but in the variety dzspalatus the ribbing approaches the beaks more nearly. The type of the latter has been carefully compared, and the ears and surface agree exactly with those of the decemnarius form. Large valves of the latter attain a height and width of sixty- eight millimetres; the type of dspalatus measures twenty-four millimetres. The cardinal crura are parallel with the hinge-line and moderately developed. The byssal notch is wide and conspicuous, the posterior ears small. In sculpture this form almost exactly parallels the recent northwest American P. hericeus in its mutations. Pecten (Chlamys) coccymelus n. s. PLATE 34, FIGURE I. Miocene of Plum Point, Maryland; Clark. Shell small, ovate, inflated, strongly sculptured, with unequal ears; disk with eighteen narrow, high, compressed ribs, with wider interspaces, which near the basal margin carry one or two very small radial threads; the backs of the ribs support numerous high, evenly spaced, distally guttered, small spines ; in the interspaces only transverse sculpture of wavy incremental lines ; TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA NI 4S to submargins small, narrow, with fine, beaded radial threads, which in the left valve also extend over the ears ; hinge-line short, the cardinal crura developed, sharply cross-striated ; auricular crura present; interior of the disk fluted in harmony with the external ribs. Alt. 30, lat. 25, semidiam. 5 mm. A single left valve of this elegant species was obtained. From the young of P. Madisonius, which sometimes approach it, it is easily distinguished by its more oval and inflated form, nearly smooth interspaces, and compressed ribs. Pecten (Chlamys) Harrisii n. s. PLATE 34, FIGURE 24. Pliocene marls of the Caloosahatchie River; Dall and Willcox. Shell strong, rounded, with seventeen coarse, rounded ribs with narrower interspaces, overrun by close-set, prominent, slightly wavy, strong concentric lamellation ; near the basal margin the ribs and interspaces are marked with a few sharp radial striae; submargins and ears with smaller radial threads similarly lamellose; notch narrow, deep; ctenolium present, short; interior of the disk strongly fluted, lirate; cardinal crura strong, auricular crura feeble. Alt. and lat. 31, semidiam. 7 mm. A single adult right valve and numerous immature ones were obtained. The valve figured is a little irregular. The young shells are proportion- ately flatter and with wider ears. They have, as often observed in the young of P. exasperatus, in some cases three or four of the ribs more prominent than the rest, and the lamellation worn off from the tops of the ribs or in- complete there. The species is named in honor of Professor G. D. Harris, of Cornell University, whose work on the Eocene fossils of the Southern States is well known. Pecten (Chlamys) exasperatus Sowerby. ? Pecten muscosus Gray, Wood's Ind. Test. Suppl., pl. 2, fig. 2, 1828; Sby., Thesaur. Conch., Pecten, p. 66, pl. xix., fig. 225, 1843; Reeve, Conch. Icon., viii., pl. 16, fig. GoW 1858.5.“ South oeasta: Pecten exasperatus Sby., Thesaur. Conch, 1., p. 54, pl. 18, figs. 183, 184, 186, 1843; Reeve, Conch. Icon., viii., pl. 2, figs. 7, 8a@—0, 1852; Dall, Bull. U. S. Nat. Mus., No. 37, p. 34, 1889. ‘‘ Mediterranean.’’ Pecten trivadiatus Reeve, Conch. Icon., viil., pl. 28, fig. 120, 1853 ; not of Miller, Zool. Dan., ii., p. 25, 1788. Pecten cretatus Reeve, of. cét., pl. 29, figs. 129 a—0, 1853. Pecten fuscopurpureus Conr., Journ. Acad, Nat. Sci. Phila., N.S., 1., pp. 209, 280, pl. 39, fig. 10, 1849. Tampa, Fla, FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA Pliocene of Costa Rica, Gabb, and of the Caloosahatchie marl at Shell Creek, Willcox; Pleistocene of Florida, South Carolina (Simmons Bluff), and of the Antilles; living from Cape Hatteras, North Carolina, to Guadelupe Island, West Indies. The figures given of mzwscosus disclose no differences in the minor sculp- ture or the number of ribs, and there are no discrepancies in the description, compared with that of exasperatus. The locality originally given for the latter has not been confirmed, and that given for mwscosus may prove erroneous. In this case, the latter name would take precedence. I have little doubt of their identity, but do not unite them because I have seen no authentic speci- mens of 7uscosus. The present species is moderately tumid, and has a scabrous sculpture besides traces of the Camptonectes striation. The backs of the ribs are set, in perfect specimens, with small, sometimes clavate spines, and there are from one to four fine threads on each side of the main keel which are usually more or less prickly. The middle of the interspaces is, however, usually free from the radial sculpture. Adult specimens with the spines considerably worn are such as Conrad called /fuscopurpureus. The colors of the shell are very varied, including brown, white, yellow, pink, and various shades of red, either simply unicolored or mottled. In the mottled brown ones it is common to see from three to five of the ribs uniformly white from end to end, or of a lighter color than the rest; this forms the ¢rradzatus type. I have examined sixty-nine adult valves, of which ten had seventeen ribs, thirty-three had eighteen ribs, twenty-three had nineteen ribs, and three had twenty ribs; the normal number, therefore, being eighteen to nineteen. The young shells are more rotund than the adults, and their ears are proportionately more con- spicuous. Guppy (Geol. Journ., xxii., p. 294) cites this species as occurring in the Oligocene of Jamaica, but the specimens he refers to present certain differences and are probably distinct. Pecten (Chlamys) ornatus Lamarck. Pecten ornatus Lam., An. s. Vert., vi., p. 176, 1819; Reeve, Conch. Iconica, xix., fig. 68, 1853. ? Ostrea sauciata Gmelin, Syst. Nat., vi., p. 3328, 1792; Chemn., Conch. Cab., vii., p- 345, pl. 69, fig. H. ? Chlamys Benedicti Verrill and Bush, Trans. Conn. Acad., x., p. 74, 1897. Pleistocene of the Florida Keys and the raised reefs of the Antilles; TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA 744 living throughout the West Indies at depths of one hundred fathoms or less, and extending from Bahia, Brazil, to the shores of the Gulf of Mexico, and north to the vicinity of Cape Lookout, North Carolina, in from fifteen to fifty- two fathoms. Also (P. Benedicti), dead, off shore in lat. 40° 9’ N., lon. 67° 9’ W., in thirteen hundred and fifty-six fathoms (?). Also in the Red Sea (?). This elegant species (to which P. mzaltisgquamatus Dunker, of Cuba, seems closely allied) is extremely variable in color and surface sculpture, and has some relations to P. membranosus. The shell which has received the name of Benedicti is only six millimetres in height and possesses no adult characters. Similar shells are, however, rather common in places in the Gulf of Mexico and West Indies, where P. ornatus abounds, and, after comparison with the umbones of half-grown orzatus, 1 am disposed to think the two should be united. Pecten (Chlamys) indecisus n. s. PLATE 34, FIGURE 3. Vicksburgian Oligocene at Archer and vicinity, Alachua County; as silicious pseudomorphs at Martin Station, Marion County; at a depth of two hundred and twenty-five feet in the artesian well, Ponce de Leon Hotel, St. Augustine; and in the Tampa limestone of the Hillsborough River, near Tampa, Florida; Dall and Willcox. Shell thin, moderately convex, ovate, with twenty-six to thirty-four small, low, simple, entire ribs separated by about equal interspaces and having a ten- dency, especially in the left valve (which is slightly more convex than the other), to become obsolete distally; transverse sculpture only of lines of growth, Camptonectes striation present, more conspicuous in the smoother specimens; ears small, unequal, the posterior smaller; byssal ear with a well- marked notch and conspicuous fasciole, above which are about six partly scabrous riblets, becoming stronger dorsally ; interior lirate, the lirae stronger near the margin; ctenolium present; cardinal crura well developed, cross- striated. Alt. of figured specimen 16, of adult 31, lat. of adult 28 mm. This is a very interesting species which retains the outline of Chlamys while at times it assumes the characters of Azzustum. Some specimens are almost ribless, except on the umbones, and in this state the species would belong to the “subgenus” Zzssopecten Verrill; in others the ribs are well developed and continuous down to the very margin, which they then crenulate ; in which state the shell is a typical Ch/amys. In most of its shell characters it is intermediate between the two subgenera, Ch/amys and Amusium. Just FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA 745 over the line, and separated from the present species more by its outline than by any other important character, is the shell I have called Aznaszam ocalanum, all of which, with the aid of A. Lyonz Gabb, form a complete connecting series between the most typical Azzusewm and undoubted Chlamys. Pecten (Plagioctenium) gibbus Linné. Ostrea gibba L., Syst. Nat., Ed. x., No. 172, p. 698, 1758; Ed. xii., No. 203, p. 1147, 1767. Jamaica. Not Ostvea gibba Born, Test. Vindo., p. 107, 1780; nor Pecten rubicundus gibbosus Ch., Conch. Cab., vil., p. 321, pl. 65, figs. 619-20, 1784 ; nor of Dillwyn, Cat. Rec. Sh., i., p. 267, 1817 (in part). Ostrea lutea Gmelin, Syst. Nat., vi., p. 3320; + O plana Gmelin, 7. c.; + O. flabellum Gmel., op. czt., p. 3321. Pecten gibbus Sowerby, Thes. Conch., 1., fig. 17 (only), 1843. Pecten gibbus Reeve, Conch. Icon., pl. 9, figs. 37 4, 37 ¢, not fig. 37 a, 1852. Pecten Soverbii Guilding, 1826, not of Reeve, 1852. Pecten dislocatus Say, Journ. Acad. Nat. Sci. Phila., i1., p. 260, 1822; Am. Conch., lvi., fig. 2, 2@, 1834. Pecten purpuratus Conrad, Am. Mar. Conch., p. 10, pl. ii., fig. 1, 1831 ; DeKay, Zool. N. Y., v., p- 174, 1843 ; not of Lamarck. -Pecten dislocatus Holmes, Post-Pl. Fos. S. Car., p. 13, pl. il., fig. 13, 1858. Pecten circularis Guppy, Paria Fauna, p. 155, 1877 ; not of Sowerby. Pecten gibbus Orb., Moll. Cuba, ii., p. 352, 1845; Krebs, W. I. Mar. Sh., p. 134, 1864 ; Arango, Fauna Mal. Cubana, ii., p. 270, 1878. Pecten irradians var. dislocatus Dall, Bull. U.S. Nat. Mus., No. 37, p. 34, No. 24, 1889. Pecten nucleus Heilprin, Trans. Wagner Inst.,i., p. 102, 1886. Fossil in the later Miocene of the Nansemond River, Suffolk, Virginia, Burns; in the Pliocene of Florida, in the Caloosahatchie marls on the Caloosa- hatchie, Shell Creek, Myakka River, and Alligator Creek, Willcox and Dall ; in the Pleistocene of North Creek, Osprey, Florida, Dall, and of the Caro- linas; also in the raised coral reefs of the Antilles. The Miocene specimens are of the typical variety g7dbus; the Caloosahatchie marls contain var. gzbbus and var. amplicostatus in about equal numbers; the Pleistocene of North Creek has var. evbdus and var. borealis, an indication of the more southerly extension of the latter during the low temperatures of that epoch. This species is at present widely distributed, and is found living from Cape Hatteras south to the Greater Antilles and Brazil, and on the continental shore to Vera Cruz and the Bay of Campeachy; also on the northwest coast of Africa, according to various authors. TRANSACTIONS OF WAGNER 746 TERTIARY FAUNA OF FLORIDA Since the original description of Linné was based on Jamaican specimens figured by Browne,* there can be no question as to the proper application of the specific name. The matter has been confused (in spite of Linne’s state- ment that the ribs are smooth) by the inclusion of a distinct form with striated ribs—figured by Born and Chemnitz and identified by Hanley with P. gzbdus, but more recently described by Fischer—from Guadelupe, under the name of P. Schrammi. Wt is true that there are occasional microscopic radial strize on the ribs of P. dislocatus or gibbus, but these do not amount to the strong striation indicated by the figures of Sowerby and Fischer. The specific name gibbus, being the oldest, must be adopted for the species. Its identity was recognized by both Gould and Stimpson, and cannot be doubted by any one who has the privilege of studying a large geographical series. Several fairly . recognizable varieties exist, and for convenience will retain their familiar names. The differences appear to be due partly to /aditat and partly to sztus, In order to test the range of variation in sculpture, I have counted the ribs on two hundred and thirty-five specimens, carefully segregating the varieties, though, necessarily, there was a marked proportion which might have been referred to either of two varieties with equal propriety. In order that the test might be as exact as practicable, the ribs on the left valve, when both were present, were selected for counting; the ridges marking the borders of the submargins were counted as ribs, the riblets of the submargins were not counted, and no specimens less than twenty millimetres in height were used. ° Pecten gibbus var. dislocatus Say (—gzbdus s. s.). Miocene to recent. The variety ds/ocatus should be called variety gzddus, since it is the typical form described by Linné, but I retain in this place the more familiar name for temporary convenience. Its range extends from Cape Hatteras to Cape St. Roque in northeastern Brazil, and probably to the Amazon, and it occurs also, if the dealers’ labels can be trusted, on the west coast of Africa. A specimen said to be African is variegated with gray and white, and has twenty ribs; of one hundred and fifty-one American and Antillean specimens three had eighteen ribs ; thirty-six, nineteen ribs ; fifty-five, twenty ribs; thirty- two, twenty-one ribs; ten, twenty-two ribs; and one, twenty-three ribs. It may be said, therefore, that the normal number of ribs for this variety is from * P. Browne, Civil and Nat. Hist. Jamaica, p. 41, pl. 40, fig. 10, 1756. FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA 747 nineteen to twenty-two. It has a preference for quiet water, and generally attaches itself to hard substances,—coral, vermetus rock, and stones,—and has a wide range of coloration, usually bright. Of the fossil specimens nine had seventeen ribs; fifteen, eighteen ribs; seven, nineteen ribs; four, twenty ribs; four, twenty-one ribs; and one, twenty-two ribs; thus showing a slight ten- dency towards fewer ribs than in the recent specimens. Pecten gibbus var. amplicostatus Dall. Pliocene to recent. This differs from the typical gzbdus by its fewer and broader ribs. It is about the same size as the type, and occurs chiefly west of the Mississippi, on the Texas coast, and south to Carthagena. It is usually white or nearly white on the right valve, and grayish with mottlings of white on the left valve. Of fourteen specimens, one had twelve; two, fourteen; four, fifteen; and seven, sixteen ribs. It is quite tumid and very solid, and probably inhabits coral or rocky bottom. Of the fossils one had fourteen; ten, fifteen; and sixteen, sixteen ribs. Pecten gibbus var. nucleus Born. Ostrea nucleus Born, Test. Vind., p. 107, pl. 7, fig. 2, 1780. Pecten gibbosus variegatus, etc., Chemn., Conch. Cab., vii., p. 323, pl. 65, figs. 621 a—d, 1784. Ostrea turgida Gmelin, Syst. Nat., vi., p. 3327, 1792; Lam., An. s. Vert., vi., p. 167, 1819 ; fide Hanley. 2 Ostrea conspersa Gmelin, p. 3320, -+ O. florida Gmelin, p. 3330, + O. guttata Gmelin, P- 3339, 1792. Recent. This is a small, thin, polished form, usually variegated with gray, white, and dark brown, and having twenty-one to twenty-three ribs. Its peculiarities are due to the fact that it attaches itself to fuci rather than hard objects. Its range extends from the Florida Keys through the Antilles. This form was not found in the Caloosahatchie marls. Pecten gibbus var. borealis Say. Pecten borealis Say, Journ. Acad. Nat. Sci. Phila., ii., p. 260, 1822. Pleistocene and recent. This is the large, thin, dark-colored form of the New England coast, ordinarily known as wradians Lamarck. It usually has fewer ribs than the TRANSACTIONS OF WAGNER 748 TERTIARY FAUNA OF FLORIDA typical zvradians, a thinner shell, and more conspicuous concentric lamelle. It is also rather more compressed. Of seventeen specimens two had sixteen, eleven seventeen, and the remainder eighteen ribs. It may be variegated with orange, gray, dark brown, or olive and white, but on the whole constantly averages darker than the southern specimens. It lives in the open bays on weedy or pebbly bottom. A Pleistocene specimen had nineteen ribs. Pecten gibbus var. irradians Lamarck. FPecten trradians Lam., An. s. Vert., vi., p. 173, 1819. Fecten concentricus Say, Journ. Acad. Nat. Sci. Phila., p. 259, 1822. Fecten turgidus Sowerby, Gen., xxxi., fig. 1, 1829 ; not of Lamarck. Pleistocene and recent. This is the southern and typical form of which doreals is the northern geographical race. It extends from New Jersey, which is Say’s typical locality, south to Georgia and Texas. It lives in open water and usually at a greater depth than the typical deslocatus (= gibbus), and never assumes the bright colors of that shallow-water form, though occasionally variegated in the same manner with dull red. In general its colors are those of the variety borealis. Twenty-two specimens had eighteen ribs; twenty-four, nineteen ribs; twelve, twenty ribs; three, twenty-one ribs; and four, twenty-two ribs. There is some variation in the roundness or angulation of the sides of the ribs, and there are rarely fine longitudinal striz on the backs of the ribs. The normal number of ribs may be regarded as eighteen to twenty in this variety. The fossils showed nineteen to twenty-two ribs. Taking all the varieties together, the generalization may be fairly made that in the Pliocene the proportion of specimens with less than nineteen ribs is decidedly larger than among the recent shells. The variations in the fossils parallel those of the living forms; the concentric sculpture may be weaker or stronger, may be visible on the backs of the ribs or only in the interspaces. The ribs may be more or less emphatic, rounded or flat-topped with lateral angles. In the latter case the concentric sculpture sometimes stops short at the angle, leaving the unworn back of the rib smooth, as if the concentric lamella had been worn off. In this case, which is the most conspicuous of the various mutations, the ribs appear laterally fringed. All the species of this group, recent or fossil, show this mutation occasionally, though it is rarer’ among the recent shells than among the fossils. FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA Pecten (Plagioctenium) eboreus Conrad. Fecten eboreus Conr., Am. Journ. Sci., xxiii., p. 341, 1833; Fos. Med. Tert., p. 48, pl. Xxiil., fig. 2, and xxiv., fig. 3, 1840. Pecten vicenarius Conr., Proc. Acad. Nat. Sci. Phila., i., p. 306, 1843. (Immature shell.) FPecten Flolbrookit Ravenel, Proc. Acad. Nat. Sci., ii., p. 96, 1844. ? Pecten micropleura H. C. Lea, Trans. Am. Phil. Soc., ix., p. 245, pl. 35, fig. 32, 1846. (Young shell.) Pecten coniparilis Tuomey and Holmes, Pleioc. Fos. S. Car., p. 29, pl. 11, figs. 6-10, 1855. Pecten yorkensis Conr., Am. Journ. Conch., iii., p. 189-90, 1867. Fecten solarioides Heilprin, Trans. Wagner Inst., i., pp. 99, 103, 1887. Fossil in the Miocene of Virginia near Suffolk (type), at the north end of the Dismal Swamp, at Snow Hill, at City Point, at Petersburg, in Prince George County, etc.; of North Carolina at Wilmington, and in Duplin County, near and at the Natural Well; of South Carolina at Darlington (comparilis) and Smith’s on Goose Creek ; and at Alum Bluff and De Land Florida. Also in the Pliocene of South Carolina on the Waccamaw River , (Johnson) and in the Caloosahatchie marls of Florida on Shell Creek and the Caloosa River; Willcox and Dall. Lecten micropleura Lea may be the young of P. marylandicus Wagner, rather than of edorews. It is an immature shell, as is wcenarius ; neither has assumed adult characters. The rise and progress of this type affords an interesting paleontologic study. The young always have the ribs clean cut and squarely channelled and more or less rectangular in section. They also usually have more ribs than the adult, as some one or two on the border of the submargins are apt to become obsolete with growth, though distinct in the young. The usual phases noted under P. gidéus (of which this form is a pre- cursor) are equally characteristic of edoreus. In the adult the ribs may be low or high, rounded or squarish, with the concentric-sculpture equally strong over the whole surface or obsolete on the backs of the ribs, the lamella feeble and distinct or close and prominent, or the surface sculpture may be almost wholly obsolete. The right valve usually shows one more rib than the left. The radial sculpture on the ears and submargins varies in strength. An examination of eighty-seven specimens resulted in showing that one had seventeen ribs, one eighteen, two nineteen, four twenty, fourteen twenty-one, nineteen twenty-two, eighteen twenty-three, fifteen twenty-four, seven twenty- TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA 75° five, three twenty-six, and three twenty-seven ribs. The normal number of ribs for this species would therefore seem to be twenty-one to twenty-five. In the basal Miocene, as at Darlington, South Carolina, the adults of this species show radial threads towards the margin, which, reticulating with the concentric sculpture, give the shell a little the look of Lyropecten, like edgecombensis, and, in fact, the shells are intermediate between the Lyropectens and Plagioctenium. The latter section has its characters well in equilibrium hardly before the recent fauna, though in this series they can be seen in the making. The different mutations, though intergrading considerably, may, for con- venience, be distributed as follows: Pecten eboreus var. darlingtonensis Dall. Miocene of Darlington, South Carolina. Shell large, radially striate on the disk near the margin; the ribs angular, well marked, twenty-one to twenty-four; the concentric sculpture fine. Pecten eboreus var. eboreus Conrad. Miocene of Suffolk, Nansemond River, Virginia. Shell large, with no radial striz on the disk; ribs low, rounded, with shallow interspaces, twenty-three to twenty-seven; concentric sculpture distant, feeble. Pecten eboreus var. yorkensis Conrad. Miocene of York River, Virginia. Like variety eboreus, but with the ribs more rectangular in section, twenty- one to twenty-five. Pecten eboreus var. comparilis Tuomey and Holmes. Miocene of South Carolina. Shell stunted, rather convex; the backs of the strong rectangular ribs bare, the interspaces and sides of the ribs with strong, crowded, concentric lamelle; twenty-three ribs, the interspaces deeply notched at the margin. This form bears to the typical edorews much such a relation as, in P. gibbus, variety dislocatus does to variety radians. Pecten eboreus var. solarioides Heilprin. Pliocene marls of Florida. Shell large, like variety eboreus, but the ribs squarish and distant, nineteen or twenty. FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA 731 Pecten eboreus var. senescens Dall. PLATE 29, FIGURE 5. Pliocene of the Waccamaw beds, South Carolina; Johnson. Shell of moderate size, rather convex ; ribs (twenty-three) obsolete exter- nally, their lire strong within; the concentric sculpture fine, chiefly visible in the interspaces. Alt. 60, lat. 62, diam. 15 mm. The posterior ear is a little more oblique in my specimen than in any of the typical edorews I have noticed, but the characters in general are so close that I hesitate to regard the form as of specific rank. Subgenus PSEUDAMUSIUM H. and A. Adams. Pseudamusium H. and A. Adams (after Klein), Gen. Rec. Moll., ii., p. 553, 1858. (Type P. hybridius Gmelin.) Pseudamusium Klein, Tent. Ostr., p. 134, pl. ix., fig. 11, 1753. Sole species. /ecten levis, variegatus, etc., of Lister, pl. 173, fig. 10; Verrill, Trans. Conn. Acad., x., p. 60, 1897. Camp tonectes (Agassiz) Meek, S. I. Checkl. Jur. Fos., p. 39, 1864. Eburneopecten Conrad, Am. Journ. Conch., i., pp. 140, 1900, 1865. The type of this group is a very rare shell, which is chiefly found in old collections, and was figured by Lister, from whom Klein copied his figure. Since H. and A. Adams accorded Klein a place as a binomial author and cited the genus as his, it follows that Klein’s type and sole example was for them necessarily the type of Psewdamusium, though they did not cite a type, and included in their list several incongruous species. But as the evidence is conclusive that Klein did not adopt the binomial system of his rival Linné, the subgenus can only date from H. and A. Adams’s habilitation of it in 1858. The Listerian shell on which Klein based his name is identified by the elder Sowerby and by Hanley with P. evoticus Chemnitz (Conch. Cab., xi., pl. 207, figs. 2037-8) and was named binomially by Gmelin, who called it P. hybridus in 1792, which ts cited in their list by the brothers Adams. There is little doubt that it is also the P. dispar of Lamarck. As the shell is rare in collections, a summary of its characters may be useful. The surface is nearly smooth in the adult, the left valve being radially and the right valve concentrically feebly sculptured. The latter is nearly flat, with a well-developed ctenolium and byssal notch; the ears in both valves are small and have stronger sculpture than the disk. The surface has the Camp- tonectes striation, most evident on the submargins. The hinge is simple, with traces of the provinculum ; the cardinal crura in the left valve feeble and close TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA 152 to and nearly parallel with the cardinal margin; the auricular crura are present, but there are no lire. The margin of the valves is entire. The colors are variegated and bright, recalling those of some deep-water species. The form of the shell is nearly orbicular, moderately convex, and the height and width of the disk is about an inch (twenty-five millimetres) in the largest valves I have seen. It is supposed to come from the west coast of Africa. The characteristics which separate this type from the deep-water forms for which Verrill has proposed the name Cyclopecten are the direct result of the environment, producing a thinner and less calcareous shell, more delicate sculpture, and, as a rule, paler coloration. Those species of Cyclopecten which range from comparatively shallow to very deep water, like P. alaskensts Dall, have, in the shallow-water specimens, the margin of the right valve solid, meeting the left valve evenly; while those from very deep water have it less calcified and consequently flexible. Otherwise the shells do not differ at all, and the character not being of specific rank, it would seem is hardly available for subgeneric distinctions. Camptonectes and its synonyme, Lburneopecten Conrad, are simply unribbed species of this group. Pecten (Pseudamusium) calvatus Morton. Pecten calvatus Morton, Syn. Org. Rem., p. 58, pl. x., fig. 3, 1834. Original locality Eutaw Springs, South Carolina, Conrad; also in the Jacksonian of Alabama and at Hatchetigbee Bluff in the Chickasawan, Burns. There are two extremely similar species of Psewdamusium in the southern Eocene; both are smooth except for Camptonectes striation, both are nearly orbicular when adult and more ovoid when young, both have the byssal ear more or less radiated. They have been more or less confused, and the original type of calvatus appears to be lost. However, there is one character by which they may be distinguished: the present species has equal or almost equal ears, and the distal cardinal angle of the posterior ear is nearly a right angle, agreeing with Morton’s figure; the other species, P. scintillatus Conr., has the ears distinctly unequal and the posterior ear obliquely truncated. It is also, in most cases, a little more elongated. Pecten (Pseudamusium) scintillatus Conrad. Pecten (Eburneopecten) scintillatus Conrad, Am. Journ. Conch., 1., p. 140, pl. to, fig. 4, 1865. (Young shell.) Camptonectes scintillatus Conr., S. 1. Checkl. Eoc. Fos., p. 23, 1866. Camptonectes claibornensts Cony., op. cit., p. 23, 1866 (name only). FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA USS Pecten claibornensis Harris, Rep. Geol. Surv. Ark., 1892, ii., p. 145.; Proc. Acad. Nat. Sci. Phila. for 1896, p. 470 (name only), pl. xviii., figs. 1, 2, 1896. Pseudamusium claibornense Harris, Bull. Pal., 9, p. 43, pl. 7, fig. 1, 1897. Chickasawan (or Lignitic) Eocene of Hachetigbee Bluff, Alabama, of the Wahtubbee hills, Clarke County, Mississippi, and at Enterprise, Mississippi; Claibornian of St. Maurice, Louisiana, and of the bluff at Claiborne, Alabama; Jacksonian (green marl bed), Jackson, Mississippi, and Clarke County, Missis- sippi; Burns and L. C. Johnson. The specimen described as scinéillatus by Conrad is very young and more oval, and with the discrepancies of the ears less marked, than in adult speci- mens such as were figured by Harris, who also suggests the relationship, which a large series of different ages enables me to confirm. The distinctions between this species and P. ca/vatus are mentioned in the remarks under the head of that species. The Camptonectes striation is more marked in the young, but rather variable as between individuals. This species is the type of Conrad’s subgenus Aéurneopecten, which he afterwards regarded as a synonyme of Camptonectes. FP. claibornensis, as such, has never received a formal diag- nosis, though it has been referred to and figured several times on the strength of Conrad’s manuscript label in the Academy’s collection. Pecten (Pseudamusium) frontalis Dall. Pecten Rogerst Clark, Bull. U.S. Geol. Surv., No. 141, p. 85, pl. 34, figs. 2a, 6, c, 1896; Johns Hopkins Un. Circ., xv., p: 5, 1895. Not P. Rogers? Conrad, Journ. Acad. Nat. Sci. Phila., vii., p. 151, 1834. Eocene of Potomac Creek, Front Royal, Virginia, Clark; Jacksonian of Garland’s Creek, Clarke County, near Shubuta, Mississippi, Burns. The specimen described by Clark is young, only eighteen millimetres in height, but Burns obtained specimens twenty-nine millimetres high by twenty- eight wide in Mississippi. The radial sculpture is obsolete near the centre of the disk and on the beaks, but well marked near the margin. There are about seventy small, low, flattened riblets separated by narrower grooves. The ears are small and the posterior ear smaller and obliquely truncate. The shell is moderately convex and recalls P. choctavensis Aldr., but with much feebler sculpture. : Pecten (Pseudamusium) cerinus Conrad. Fecten cerinus Conr., Am. Journ. Conch., v., p. 39, pl. 2, fig. 2, 1869. Miocene of Charles County, Maryland, Cope; Ashley River phosphate rock, South Carolina, Dall. TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA 754 Shell small, thin, polished, compressed; left valve more convex, with about twenty faint, flat, rather irregular obsolete ribs, separated by narrower, shallow sulci, the whole surface with minute Camptonectes striation; right valve with concentric incremental lines and a few faint threads near the beaks and anterior submargin; ears small, subequal; ctenolium present; cardinal and auricular crura developed; interior of left valve faintly fluted, but without lire. Alt. 10, lat. 18 mm. In some of the specimens there are a few feeble concentric undulations near the beak of the left valve. ? Section Hyalopecten Verrill. flyalopecten Vernill, Trans. Conn. Acad., x., p. 71, 1897. Type P. widatus Vernill, of. ctt., Vi., p. 444, 1885; = P. fragilis Jeffreys, Ann. Mag. Nat. Hist.; p. 424, 1876, -- Flyalopecten dilectus Verr. and Bush, Trans. Conn. Acad., x., p. 80, 1897. This section differs from the ordinary abyssal Psewdamusium in being concentrically undulated, and from the thin, smooth, shallow-water forms like P. gronlandicus in the absence of the Camptonectes striation. These features are barely of more than specific value, as they appear to be generally inter- changeable, like other surface characters in this genus. The types of Jef freys’s P. fragilis are in part in the United States National Museum. They agree perfectly with his description and figures (P. Z. S., 1879, p. 561, pl. xlv., fig. 1 [inner and outer views]). The first specimens obtained were frag- mentary, as was the case with P. wzdatus Verrill. I have compared the speci- mens received from both authors with care, and consider them conspecific. P. dilectus is complete, and, except that it is a younger and smaller shell, I have been unable to detect any differences, even of a varietal nature. On the other hand, the specimen to which Professor Verrill has given the name fragilis Jeffreys is a perfectly distinct species with marked characters, as noted by Professor Verrill (of. cz¢., p. 81). Jeffreys in his original description describes “cc his shell (left valve) as having “ numerous fine and raised striae’ which “ radiate from the beak and cover the whole surface.” How, then, Professor Verrill should come to regard a shell “ distinctly undulated but not otherwise sculpt- ured” as the species of Jeffreys is a mystery which I cannot solve. At all events, they are perfectly distinct, and the P fragilis Verrill, non Jeffreys, may take the specific name of ewcymatus. It should be observed that the “raised striz,”’ or threads, described by Jeffreys, are more abundant and more constant on the left valve; on the right valve they are often nearly obsolete, FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA NS and on the left valve the different individuals differ in the amount of their _radiation. Pecten (Hyalopecten) sp. indet. Lower Miocene of the Ashley River, South Carolina, in the so-called “ phosphate rock.” Valves of a species too imperfect for satisfactory description, yet showing distinctly a thin, undulated, and probably radially striate shell, of about the size of half-grown P. fragilis (circa eight millimetres in altitude), were found in the rock above mentioned. The shells were crushed and their undulations flattened down during fossilization, and the chief character which appears to have distinguished them from P. /ragi/is is that the undulations were higher and sharper and the form perhaps more ovate. Still, this group is so singular, and its discovery in a fossil state so interesting, that I feel it should be recorded. Pecten (Pseudamusium) Guppyi Dall. PLATE 34, FIGURES 12, 13. This species has already been cited (p. 718) as occurring in the Alum Bluff beds at Oak Grove, Santa Rosa County, Florida, as well as in the Oligo- cene and later formations of the Antilles and Costa Rica. Subgenus AMUSIUM (Bolten) Schumacher. Amusium (Rumphius, 1705) Bolten, Mus. Bolt., 1st ed., p. 165, 1798 (no description) ; Schum., Essai, p. 117, 1817; Dall, Bull. Mus. Comp. Zool., xii., No. 6, p. 207, 1886. Pleuronectta Swainson, Malac., p. 388, 1840. Type Ostrea pleuronectes Linné. Pecten (Amusium) precursor n. s. Oligocene of the Chipola beds at Alum Bluff and on the Chipola River and elsewhere in these beds; Burns and Dall. There are several species of Amstum ranging from the Oligocene to the recent fauna in this region. In general they appear extremely similar, so much so that such figures as are ordinarily given would show no differential characters. By careful and repeated study I find myself able to separate them by the umbonal sculpture, which differs in the different forms as follows : Nepionic shell perfectly smooth externally. 1. Shell more or less ovate: P. papyraceus Gabb. 2. Shell very large, orbicular: P. Morton Rav. 2 13 TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA NI on oO Nepionic left valve with obsolete radii and often feeble concentric undulations: P. precursor Dall. Nepionic left valve with distinct flattened ribs with shallow channelled inter- spaces crossed by concentric, evenly spaced, not crowded, elevated lines: P. Lyont Gabb. Left valve of the adult with obsolete rounded ribs extending, in the adult, well over the middle of the disk: P. ocalanus Dall. P. precursor is nearly as large as P. Mortoni, but slightly rougher and more convex when adult, the young are nearly orbicular; a distinct trace of Camptonectes striation, near the beak and submargins, may be discerned with a magnifier in a good light. Alt. 110, lat. 123, diam. 20 mm. The right valve is much flatter than the other. As the material is much broken up, it seemed hardly worth while to figure it. Pecten (Amusium) ocalanus n. s. PLATE 29, FIGURE 2. Oligocene of the Vicksburgian at Natural Bridge, Alachua County; at various localities in Levy County; at Arredonda and Archer; Newnansville and Johnson’s lime sink; and in the Nummulitic horizon at Ocala and Martin Station, Marion County, Florida; also in the Vicksburgian of Alabama; Dall, Burns, and Willcox. Shell of moderate size, nearly equivalve, quite inequilateral, moderately convex; right valve with the disk nearly smooth, posterior margin produced ; ears subequal, nearly smooth, their outer angles a little raised, so that the cardinal margins form a very obtuse angle at the beak; byssal sinus repre- sented by a marked flexure but not a distinct notch; left valve similar, slightly more convex, with about eighteen obsolete rounded ribs, separated by narrow, shallow grooves, sharpest near the beak, radiating nearly to the basal margin but becoming less visible there and at the submargins; ears ver- tically striated, subequal; interior of the disk with about twenty-one pairs of well-marked lirze similar in each valve; hinge with developed cross-striated cardinal crura, auricular crura present; margins of the valves smooth, not crenulated. Alt. of figured shell 35, lat. 35; alt. of largest specimen 43 mm. The fossils vary from nearly smooth to obviously ribbed; the byssal sinus is more distinct than in the other species and sometimes verges on a notch, and there is a perceptible byssal fasciole. FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA 757 Pecten (Amusium) papyraceus Gabb. This species, described from the Tertiary of St. Domingo, appears to be identical with the recent species of the Gulf of Mexico and the Antilles. I formerly referred it to P. Morton, to which it is closely related, but it is generally less orbicular and smaller than the typical P. Mortoni, and in default of a full and completely intergrading series it is probably better to retain Gabb’s name. Pecten (Amusium) Mortoni Ravenel. Pecten Mortont Rav., Proc. Acad. Nat. Sci. Phila., ii., p. 96, 1844 ; Tuomey and Holmes, Pleioc. Fos. S. Car., p. 27, pl. 10, figs. 1,2, 1855; Emmons, Geol. N. Car., p. 281, 1858. Miocene of Fairhaven and Drum Point, Maryland; Duplin County, North Carolina; Cooper River and Goose Creek, South Carolina, and in the upper bed at Alum Bluff, Chattahoochee River, Florida; Pliocene of the Caloosa- hatchie marls on the Caloosahatchie and Shell Creek, Florida; Burns, Willcox, and Dall. Pecten (Propeamusium) alabamensis Aldrich. Pecten (Pleuronectia) alabamensis Aldr., Bull. Geol. Surv. Ala., p. 40, pl. 4, fig. 8, 1886 ; Harris, Bull. Pal., iv., p. 162, pl. 2, fig. 3, 1896. Pecten alabamensis Harris, Geol. Surv. Ark., Rep. for 1892, ii., p. 41. Pecten (Amussium) alabamensis de Gregorio, Mon. Claib. Fauna, p. 183, pl. 21, fig. 26 , 1890. Basal or Midwayan Eocene of Dale’s Branch, Matthews Landing, and Naheola, Alabama, and of Marshall’s Well, Little Rock, Arkansas. This interesting little species reaches less than five millimetres in extreme height, has the right valve concentrically striated or nearly smooth, the left with sparse, partly obsolete radial threads crossed by elevated, concentric, distant lines, with a tendency to nodulation at the intersections. Internally there are about eight or ten well-developed lirze and the auricular crura. The byssal ear has sparse radii and a distinct byssal notch. Pecten (Propeamusium) squamula Lamarck ? ? Pecten squamula Lam., Ann. du Mus., vili., p. 354, No. 3, 1806; Hist. An. s. Vert., vi., p. 183, 1819; Desh., Descr. Coq. Fos. Env. Paris, i., p. 304, pl. xlv., figs. 16-18, 1824. 2? Amusstum squanula Cossm., Ann. Soc. Roy. Mal. de Belg., xxii., p. 188, 1887. Amussium squamulum Harris, Bull. Pal., ix., p. 44, pl. 7, figs. 2, 3, 1897. Chickasawan (or Lignitic) Eocene of Wood’s Bluff, Alabama; Harris. TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA Sy On (ee) This small species is destitute of the reticulate sculpture on the left valve which characterizes P.- alabamensis, and is doubtless distinct. It has been referred by Professor Harris to Lamarck’s species. On comparing the figures of Harris and of Deshayes, the latter seem to represent a species broader and more orbicular than Professor Harris’s figures of the Wood’s Bluff shell. I have, however, not seen specimens of either. There are several closely related recent species in the deep waters of the Atlantic off the American coast and among the West Indian islands. Famity SPONDYLID. Genus SPONDYLUS Linné. Spondylus Linné, Syst. Nat., Ed. x., p. 610, 1758. Type S. gederopus L. Mediter- ranean. The species of this genus are not numerous in the American Tertiary or the recent fauna. Spondylus dumosus Morton. Plagiostoma dumosum Mort., Org. Rem., p. 59, pl. 16, fig. 8, and fig. in text, 1834. Spondylus dumosus Conr., Cat. Eoc. Fos., Am. Journ. Conch., i., p. 14, 1865. Eocene of the Jacksonian horizon, St. Stephens, Clarke County, Cocoa Post-Office, Choctaw County, etc., in Alabama; Red Bluff, Wayne County, Carson’s Creek near Shubuta, and Chickasawha River, Wayne County, Mis- sissippi; Winchell, Burns, and Johnson. This well-defined species is unusually uniform in its characters and may be easily discriminated from the next species by its longer and more con- spicuous submargins. It also seems never to reach so large a size. Spondylus bostrychites Guppy. Spondylus bifrons Sowerby, Quart. Journ. Geol. Soc., vi., p. 53, 1849; not of Goldfuss, Petref., ii., p. 99, pl. 106, figs. 10 a—e, 1835. Spondylus bostrychites Guppy, Proc. Sci. Soc. Trinidad, p. 176, 1867; Gabb, Geol. St. Domingo, p. 257, 1873. Oligocene of St. Domingo, at Ponton; of the Bowden marl, Jamaica ; of Anguilla; of White Beach, near Osprey, Florida, and in the Ballast Point silex beds, Tampa Bay, Florida. Variety chipolanus: Chipola beds on the Chipola River; lower bed at Alum Bluff, Chattahoochee River; Alum Bluff beds at Oak Grove, Santa Rosa County, and the Ballast Point silex beds, Tampa Bay, Florida. The type form of this species has a relatively small number of spinose FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA 759 ribs, the intervening ones being free from spines, longitudinally finely striate, and show when very perfect minute scales. The adult shell is rather short and rounded and less inflated than usual in the genus. The species is remark- able for its small hinge-area. In the variety cizpolanus Dall there is no radial striation on the inter- spatial ribs, but rather a concentric sculpture; there are many more spinose ribs, the shell is more oval and more inflated, and, as far as the material goes, seems to attain a larger size. It may prove distinct with more perfect speci- mens, in which case the varietal name may be taken as specific. Spondylus rotundatus Heilprin. PLATE 35, FIGURES 25, 25a. Spondylus rotundatus Heilprin, Trans. Wagner Inst., 1., pp. 99, 103, pl. 14, fig. 33, 1887. Pliocene marls of the Caloosahatchie and Shell Creel, Florida; Willcox and Dall. This fine species was represented in the original publication by a very poor figure drawn from a very imperfect lower valve, so I have had another figure prepared showing the characters. It is characterized by the presence of eight or ten primary ribs with longer spines, which are broad, spathulate, and longitudinally ridged; at the end, when perfect, the spine is decurved like a half-shut hand. Between the primaries are two or three smaller ribs densely clothed with similar but smaller and shorter spines whose backs are so close together as to almost conceal the whole surface. The cardinal area is of moderate size, triangular and twisted. The lower valve is similarly sculptured, but with less regularity. Traces of coloration indicate that the shell originally was of deep red or purple color. SS. votundatus is less similar to the recent most foliaceous specimens of S. echimatus than is the Oligocene dostrychites. Spondylus echinatus Martyn. Ostrea echinata Martyn, Univ. Conch., ii., fig. 154, 1784. Spondylus armatus Humphrey, Mus. Calon., p. 54, No. 1021, 1797. Spondylus croceus Humphrey, Mus. Calon., p. 55, No. 1022, 1797; Arango, Moll. Cubana, p- 271, 1880. Spondylus dominicensis Bolten, Mus. Bolt., 1st ed., p. 193, 1798; 2d ed., p. 135, 1819; (Chemn., vii., p. 79, pl. 45, fig. 465.) Spondylus aurantiacus Bolten, op. cit., p. 195, 1798. Spondylus americanus Lam., An. s. Vert., vi., p. 188, 1819 ; (Enc. Méth., pl. 195, figs. I, 2;) Reeve, Conch. Icon., pl. 4, fig. 17, 1856. TRANSACTIONS OF WAGNER 760 TERTIARY FAUNA OF FLORIDA Spondylus longitudinalis Lam., An. s. Vert., vi., p. 191, 1819; (Chemn., vil., p. 81, pl. 45, fig. 466 ;) Reeve, pl. 13, fig. 46, 1856. Spondylus spathuliferus Lam., op. cit., p. 191; (Enc. Méth., pl. 191, figs. 4, 6, 7 ;) Dall, Bull. U.S. Nat. Mus., No. 37, p. 32, 1889. Spondylus crassisquama Lam., op. cit., p. 191, ex parte. Spondylus arachnoides Lam., op. ctt., p. 188. Spondylus longispina Lam., op. cit., p. 189. Spondylus avicularis Lam., op. ctt., p. 190. Spondylus gilvus Reeve, Conch. Icon., pl. 11, fig. 38, 1856. Spondylus erinaceus Reeve, op. cit., fig. 39. Spondylus ictericus Reeve, op. cit., fig. 40. Spondylus ramosus Reeve, op. cit., pl. 14, fig. 51. Spondylus imbutus Reeve, op. cit., pl. 15, fig. 55. Spondylus ustulatus Reeve, op. cit., pl. 16, fig. 58. Spondylus vexillum Reeve, op. ctt., pl. 16, fig. 59. Spondylus nux Reeve, op. cit., pl. 18, fig. 64, 1856. Spondylus digitatus Reeve, op. cit., fig. 68. Spondylus echinatus Orbigny, Moll. Cuba, ii., p. 359, 1846. Spondylus folia-brassice Orbigny, op. czt., p. 358, 1846. Fossil in the Pleistocene elevated reefs of the West Indian Islands and of the continent from southeastern Florida to Brazil; and recent over the same general region, extending as far north as Cape Hatteras, North Carolina. This species has the irregularities of sculpture due to, or usually asso- ciated with, the sessile habit, and the mutations of color characteristic of many Pectinidz. To these and to the exigencies of trade imposed by dealers upon Reeve is due the multiplication of merely nominal species indicated in the preceding synonymy. The normal or most ordinary type of sculpture comprises from four to eight radial ridges from which project spines, either narrow and almost pointed, or wide and crumpled or digitate, separated by wider interspaces with smaller, sometimes spinulose, radii, to which is added a series of still finer threads, chiefly indicated by rows of small, short scales. By the continuity and regularity of the radial lines the species is separated from the otherwise quite similar S. g@deropus Linné of the Mediterranean. Specimens which have been cleaned with acid have usually lost the tertiary rows of minute scales, but they seem to be absent naturally from some specimens which have only two series of radials, the secondary ones but little spiny, and the spines comparatively sparse, long, and narrow on the primary ribs. This type forms the variety americanus. The sculpture on the fixed valve is more foliaceous FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA and less spiny than on the other. The spinosity varies greatly; some indi- viduals have almost none, others are profusely spiny, and others, again, have the spines limited almost entirely to the major ribs, which vary greatly in number. There is occasionally a distinct ctenolium in adult specimens. The colors and their distribution vary as in many Pectens. I have seen from the West Indian region but one species of large folia- ceous Spondylus (with one well-marked variety),—the present species. There is one deep-water species, common to the Mediterranean,—the Spondylus Gussont of Costa, which is small, with acicular spines, and colorless. The Eocene S. amussiopse de Gregorio is the young of Ficatula fila- mentosa Conrad. S. inornatus Whitfield, from the Miocene of New Jersey, is based on a smooth specimen of Plicatwla densata Conrad. S. estrallensis Conrad, 1857, afterwards altered to S. estvel/anus, from the Miocene of the Estrella valley, California, was based on a much-mutilated specimen of Lyro- pecten. The very imperfect type of Pecten anisopleura Conrad from North Carolina strongly resembles a Spondylus, but is too incomplete to permit of positive determination. A species doubtfully referred to this genus is men- tioned by Heilprin in his paper on the Eocene Mollusca of Texas (Proc. Acad. Nat. Sci. Phila. for 1890, p. 404). Professor Harris has figured a valve of a Spodylus from the Chickasawan or Lignitic beds of Hatchetigbee Bluff, which he doubtfully refers as a variety to S. dumosus Morton. The specimen is too imperfect to afford definite evidence, but may probably turn out to be a distinct species (cf. Bull Pal., No. 9, p. 42, pl. 6, fig. 11, 1897). Genus PLICATULA Lamarck. Plicatula Lam., Syst. An. s. Vert., p. 132, 1801. Type P. gzbbosa Lam., 0c. = P. ramosa Lam., 1819. FHarpax Parkinson, Org. Rem., 3, pl. 12, 1811 ; Brookes, Intr. Conch., p. 83, 1815. Type fH. Parkinsoni@ Bronn. Ostrenomia Conrad, Proc. Acad. Nat. Sci. Phila. for 1872, p. 216. Type O. carolinensis Conr. The only established species mentioned by Lamarck in the Systeme, where he described the genus, is the West Indian form, which he at first named P. gibdosa and wrongly identified with the Chinese Spondylus plicatus of Linné. In 1819 he arbitrarily changed the name to vamosa. Linne’s still preserved type specimen and designated habitat show that his species was not TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA the same as that of Lamarck. The latter, and not P. picata, must therefore be cited as the type of the genus. The original specific name must, of course, be retained. The .genus is easily separated from the Spondyli by the character of its hinge. It may attach itself by either valve; there is no regularity in this respect within the species. An important memoir by Deslongchamps on this group is to be found in the Trans. Soc. Linn. de Normandie, ii., 1860. Pheatula arose in the Trias and reached its maximum in the later Mesozoic. It is doubtless an offshoot from the Pectimid@, with which the characters of the hinge, the occasional auriculation, and the presence in some species of internal lire, appear to connect it. Plicatula filamentosa Conrad. Plicatula filamentosa Conrad, Fos. Tert. Form., p. 38, 1833. Phicatula Mantilli Lea, Contr. Geol., pp. 89, 90, pl. 3, fig. 68, 1833. Plicatula planata Aldrich, Journ. Nat. Hist. Soc. Cin., ix., p. 45, pl. ii., fig. 20, 1866. (Young shell.) Spondylus amusstopse Gregorio, Claib. Mon., p. 179, pl. 20, figs. 11-13, 1890. (Young shell.) Eocene of the Chickasawan or Lignitic at Hachetigbee, and of the Clai- borne sands at Claiborne, Alabama, also at Newton and Wahtubbee, Missis- sippi, and in corresponding beds in Louisiana, Burns, Johnson, Aldrich, Harris, and others; and in Lee County, Texas, Singley. This species is peculiar in its characters. When young it has fine radial striation on both valves, which may sometimes be wholly or partly spiny (mut. p/anata), and the shell is flattish ; this sculpture changes rather suddenly by an appearance of the large plications, of which the lateral ones rarely bear a few coarse spines. The radial striation continues through life in well-de- veloped specimens, and may be recognized in unworn shells. There are sometimes well-marked auricles developed near the beaks. The interior of the young, as noted by Gregorio, presents a few strong lire resembling those of Propeamusium ; these persist until middle age, especially distally, but on the disk are gradually buried in shelly matter. The thickened ends of the lire are visible longer, but gradually disappear, their position in the adult being marked by small pits. Plicatula filamentosa var. concentrica. Wahtubbee Hills, Clarke County, Mississippi; Burns. FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA This form is marked by a total disappearance of the radial striz and the development of fine, even, regularly spaced, concentric, elevated sculpture all over the shell. I should have regarded it as a distinct species had it not been for a few intergrading specimens. A fossil which may be a Picatula, but of which the hinge is not accessi- ble, is figured from the Midwayan Eocene by Harris, Bull. Pal. No. 4, p. 47, pl. 2, figs. 2, 2a, 1896. Plicatula densata Conrad. Plicatula densata Conrad, Proc. Acad. Nat. Sci. Phila., i., p. 311, 1843; Medial Tert., p. 75, pl. 43, fig. 6, 1845; Proc. Acad. Nat. Sci. Phila., xiv., p. 582, 1863. Spondylus tnornatus Whitfield, Mioc. Pal. N. J., p. 34, pl. 5, figs. 1, 2, 1895. In the Oligocene Vicksburg limestone at Archer, Florida, and the Num- mulitic horizon at Ocala, Florida, Dall and Willcox; also in the Guallava beds of Costa Rica, Hill; in the Chipola beds on the Chipola River, and in the lower bed at Alum Bluff; in the silex beds of Ballast Point, Tampa Bay, and in the Alum Bluff sands at Oak Grove, Santa Rosa County, Florida, and the Bowden marl, Bowden, Jamaica; in the Miocene marls of Cumberland County, New Jersey, at Shiloh and Jericho. This species is distinguished from the later margimata of Say by its usually rounder form and more numerous, less prominent plications. Occa- sional specimens attached to a smooth surface by a considerable area do not develop the plications, and one such has served as the type of Whitfield’s species. Plicatula gibbosa Lamarck. Plicatula gibbosa Lam., Syst. An. s. Vert., p. 132, 1801. Plicatula ramosa Lam., An. s. Vert., vi., p. 184, 1819; ? Heilprin, Trans. Wagner Inst., 1., p. 102, 1887. Phicatula cristata Gabb, Geol. St. Dom., p. 257, 1873. Plicatula vexillata Guppy, Geol. Mag., Dec. ii., vol.i., p. 444, pl. xvii., fig. 7, 1874. ? Oligocene of Jamaica, Guppy; recent in the Atlantic from Cape Hat- teras, North Carolina, south to the West Indies and Rio de la Plata, Brazil. This species is contained in the Guppy collection from Jamaica, the specimens showing the dark lines belonging to the species, but I suspect that they were obtained from a later, perhaps a Pleistocene, deposit, as the explora- tions of the Bowden marl by Messrs. Henderson and Simpson have produced only specimens of the P. densata from the Bowden horizon. TRANSACTIONS OF WAGNER 764 : TERTIARY FAUNA OF FLORIDA Plicatula marginata Say. Plicatula marginata Say, Journ. Acad. Nat. Sci. Phila., iv., pp. 136-7, pl. 9, fig. 4, 1824 ; Conrad, Fos. Med. Tert, p. 75, pl. 43, fig. 5, 1845; Tuomey and Holmes, Pleioc. Fos. S. Car., p. 24, pl. 7, figs. 11-14, 1855. Plicatula rudis H. C. Lea, Trans. Am. Phil. Soc., N.S., ix., p. 246, pl. 35, fig. 34, 1845. Miocene of Petersburg, Virginia, Lea; of Coggins Point, Virginia, E. Ruffin; of York River, Virginia, Harris; of Duplin County, North Carolina, Murfreesborough and Wilmington, North Carolina, Haldeman and Stanton; of Darlington, South Carolina, Burns; Pliocene of De Leon Springs (Wright), and of the Caloosahatchie marls on the Caloosahatchie, Shell Creek, and Alligator Creek, Dall and Willcox; of the Waccamaw River, South Carolina, Johnson; and of Cape Fear, North Carolina, Dr. Yarrow. So far as the form of the shell is concerned, this species cannot be dis- criminated from P. gzbdosa, but none of the specimens show any trace of the dark venous lines which are so characteristic of both recent and fossil speci- mens of gzdbosa. In a very large series of the recent shell a few specimens will usually be found which have a diffused brownish blush instead of the brown lines; but these are so exceptional that I have felt the present species might be separated with propriety. In both the differences of sculpture due to stfus pass through a parallel series of mutations. The genus Ostrenomia Conrad, referred to in the synonymy, is in my opinion based on a specimen of Pcatwla which incidentally grew around the stem of a Gorgonian or other round object, as there is no byssal scar. The specimens were from the Eocene of North Carolina. There are a number of Cretaceous species of P&catula, but I have been unable to find any other Tertiary forms from America cited in the literature besides those above mentioned. Famity DIMYACID 2. Genus DIMYA Rouault. Dimya grandis Dall. PLATE 35, FIGURE 8. Dimya grandis Dall, Proc. U. S. Nat. Mus., xix., No. I110, p. 328, 1896. Oligocene of St. Domingo, at the Potrero, Rio Amina; Bland. The recent D. argentea Dall has not been found fossil. The present species may not improbably hereafter be found in the Chipola beds. FREE INSTITUTE OF SCIENCE TERTIARY FAU ee D 125 NA OF FLORIDA Famity LIMID/2. Genus LIMA (Bruguiére) Cuvier. Lima Bruguiere, Enc. Méth., pl. 206, 1792; name only, no type; Cuvier, Tabl. Elém., p. 421, 1798: type Ostrea ima L., Lam. Prodr., p. 88, 1799. Mantellum Bolten, Mus. Bolt., p. 160, 1798. Limaria Link, Beschr. Rostock Samml., p. 157. Glaucion a Oken, Zool., 1815, fide Herrmannsen. Radula H. and A. Adams, Gen. Rec. Moll., ii., p. 556, 1858; not Radiula Gray, Syn. Br. Mus., p. 60, 1844. Ctenoides H. and A. Adams, of. cét., p. 557, 1858; L. scabra Born. Acesta H. and A. Adams, of. cét., p. 558, 1858; ZL. excavata Chemn. This very natural group indicated by Bruguiere derived its name from the nonbinomial writers, but was first defined and a type mentioned by Cuvier. Bolten named it without a diagnosis in the same year, and Link a few years later corrected the form of the name, after his habit. The nonbinomial names of Klein were habilitated by H. and A. Adams, but take date only from their work. The group is divisible as follows: Subgenus Zima s.s. Hinge edentulous; valves gaping, inequilateral. Section Zzmas.s. Sculpture radial, submargins impressed. ZL. “ma Linné. Section Crenoides Ads. Sculpture divaricate, submargins impressed. L. scabra Born. Section Plagiostoma Sowerby, 1814. Sculpture feeble, radial; valves subtriangular, with a deep resiliary pit. ZL. gigantea Sowerby. Section Mantellum Ads. Submargins not impressed. ZL. Azans Gmel. Subgenus Lzmatula Searles Wood, 1839. Valves closed, equilateral, more or less distinctly mesially sulcate; sculpture radial: L. swbauriculata Mtg. The group is quite ancient, and attained its climax in the Mesozoic; the Tertiary species are relatively few and rare. I have omitted some of the older forms from the list as hardly in place here. Lima (Lima) vicksburgiana n. s. PLATE 35, FIGURE 20. Vicksburgian Oligocene, at Johnson’s lime-sink, Levy County, and at La Penotiére’s hammock, near Orient, Florida; Dall. Shell of moderate size, hardly oblique, moderately gaping, elongate, radially sculptured, with thirty-five or more nearly simple radial ribs, sepa- TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA rated by slightly wider interspaces, which cover the whole surface; sub- margins slightly impressed; ears small, unequal; hinge-margin straight, basal margin slightly indented by the ribs; a slight nodulation is perceptible on the backs of the ribs. Alt. 30, lat. 23 mm. This differs from ZL. staminea Conrad (Journ. Acad. Nat. Sci. Phila., 2d Ser., 1, p. 126, pl. 13, fig. 30, 1848) in its less angular and oblique outline, more prominent ears, and stronger and more regular sculpture. Lima (Lima) tampaénsis n. s. PLATE 35, Ficure 18. : Chipolan Oligocene, near Bartow, and on the shores of Hillsborough Bay, near Tampa, Florida; Dall. Shell very inequilateral, the anterior side short, moderately gaping; the posterior side long, straight, with a wide impressed submargin ; base expanded and rounded; hinge-line very short, with very small ears, the anterior larger; pit large, triangular, not oblique; exterior with about twenty-seven narrow, smooth, rounded radial ribs separated by wider channelled interspaces; the basal margin is serrated by the sculpture; the submargins are finely striated. Alt. 35, lat. 27, diam. 14 mm. The chief characteristics of this species lie in its simple, distant, rounded ribs and the great obliquity of the valves. Lima (tampaénsis var.?) costulata n. s. PLATE 35, FIGURE 24. An imperfect valve was obtained from the Oligocene of Hillsborough Bay, near Tampa, Florida. Shell like the preceding but broader, with more numerous (thirty-five) ribs, which are separated by very narrow interspaces and in perfect specimens are probably minutely nodulous; the posterior submargin is also more deeply impressed. This is probably a distinct species, but the material is insufficient to fully define its characters, and I mention it as.a variety merely in order that it may not be lost sight of. Lima (Lima) smirna n. s. PLATE 30, FIGURE 3. Chipolan Oligocene of Hillsborough Bay, near Tampa, Florida; Dall. Shell ovate, slightly inequilateral, smooth, except for incremental lines ; FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA submargins narrow, concentrically striated, the anterior longer, with a moder- ate gape, the posterior shorter, hardly differentiated from the disk ; ears small, hinge-line short, shell very thin. Alt. 31, lat. 23, diam. ro mm. The perfectly smooth surface of this species differentiates it from any other of our Tertiary species. Lima (Mantellum) carolinensis n. s. PLATE 35, FIGURE 21. Oligocene of the Oak Grove sands, Santa Rosa County, Florida, Burns; Miocene of Darlington, South Carolina, and the Duplin Natural Well, Duplin County, North Carolina, Burns. Shell small, thin, inflated, oblique, with a moderate gape, sculptured with concentric lines of growth and rather sharp, fine, numerous, somewhat irreg- ular radial threads, obsolete on the beaks, absent from the posterior submargin and the anterior ears; submargins not impressed, beak prominent, ears small, the margin of the gape forming a concave sinuosity in front of and below the anterior beak; hinge-line short, with a very wide pit, its lower margin project- ing from the cardinal plate; interior radially striate, the basal margin slightly crenulate. Alt. 16, lat. 12, diam. 7 mm. This differs from ZL. papyria Conrad, from the Maryland Miocene, in the absence of the angle which in the latter species modifies the margin just below the anterior ear, and in the presence of dense radial striation on the anterior submargin, while in Z. papyria this region is smooth. Lima lima Linné. Ostrea lima L., Syst. Nat., Ed. x., p. 699, 1758. Pecten radula Chemnitz, Conch. Cab., vii., p. 349, pl. 68, fig. 651, 1784. Lima squamosa Lam., Syst. An. s. Vert., p. 136, 1801; An. s. Vert., vi., p. 156, 1819 ; Dall, Bull. U. S. Nat. Mus.,*No. 37, p. 36, No. 46, 1889. Pliocene of the Caloosahatchie marls, Florida, Dall; Pleistocene of the West Indies; recent on the American coast from Sarasota Bay, Florida, to Brazil, and widely distributed in foreign seas. Type of the genus. This shell seems rare in the Pliocene. Only a few small specimens were obtained. Lima (Mantellum) caloosana n. s. PLATE 28, FIGURE 3. Pliocene of the Caloosahatchie; Dall and Willcox. Shell inflated, oblique, strong, with a large anterior gape, the posterior TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA 768 margins not excavated; incremental lines strong; radial sculpture of about forty rather sharp, minutely nodulous, narrow threads, with usually wider but often somewhat irregular interspaces, sometimes carrying a slender intercalary thread or faint traces of radial striation; submargins almost free from radial sculpture, not impressed; hinge-margin short, pit large, wide, with a pro- jecting lower margin; basal margin of the valve rounded, hardly crenulated by the sculpture. Alt. 37, lat. 35, diam. 24 mm. This shell is much like the recent ZL. zzffata Gmelin, but is constantly wider, less oblique, and differs in minor details. It appears to be one of the characteristic species of the Caloosahatchie marls. Lima (Ctenoides) scabra Born. Ostrea scabra Born, Test. Mus. Vind., p. 110, 1780. Ostrea glacialis Gmelin, Syst. Nat., vi., p. 3332, 1792. ex parte. Lima aspera Chemnitz, Conch. Cab., vii., p. 352, pl. 68, fig. 652, 1784. Ostrea sagrinata (Solander MS.), Mus. Calonnianum, p. 52, 1797. Lima glacialis Lamarck, An. s. Vert., vi., p. 157, 1819; Holmes, P.-Pl. Fos. S. Car., p. 13, 1860. Lima scabra Heilprin, Trans. Wagner Inst., i., p. 120, 1887; Dall, Bull. U.S. Nat. Mus., No. 37, p. 36, No. 48, 1880. Pliocene of the Caloosahatchie, Monroe County, Florida, Heilprin, Willcox, and Dall; Pleistocene of South Carolina and the West Indies; recent from Cape Hatteras, North Carolina, to the island of Trinidad, West Indies. This well-known species occurs in excellent condition in the Pliocene marls. Lima (Ctenoides) tenera Sowerby. Lima tenera Sby., Thes. Conch., p. 84, No. 2, pl. xxi., figs. 10, 11, 1847; Dall, Bull. U.S. Nat. Mus., No. 37, p. 36, No. 47, 1889. Pliocene of the Caloosahatchie, Monroe County, Florida; Pleistocene of the West Indies; recent from Cedar Keys, Florida, south to Barbados, West Indies. A single valve of this form, which is, perhaps, little more than a variety of L. scabra, was obtained from the marls. Genus LIM AGA Bronn, em. Limea Bronn, Ital. Tert., p. 115, 1831. Ostrea strigillata Broc. Limoarca Minster, Leonh. u. Bronn, Jahrb., p. 421, 1832. Lime@a Gray, P. Z. S., 1847, p. 201. FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA 769 This genus differs from Lzma by having on each side of the resilium a number of taxodont teeth on the cardinal margin. Limezea solida n. s. PLATE 35, FIGURES 4, 5. Oligocene of the Bowden beds at Bowden, Jamaica; Henderson and Simpson. Shell minute, solid, rounded triangular, with about twelve rounded, strong, slightly granular radial ribs, separated by narrower interspaces crossed by lines of growth; submargins without radial sculpture; hinge-line short, with a small central pit, on each side of which are about eight teeth; interior radially feebly grooved, the basal margin crenulated by the ribs ; shell moderately inflated. Alt. 3.5, lat. 3.3, diam. 2.5 mm. This little shell is related to the Z. Bronnitana Dall of the recent fauna, but is distinguished from it by its narrower and more solid hinge, with a dis- tinctly smaller resiliary pit and heavier and more solid shell. Besides the species above discussed, the following members of this family have been reported from our Tertiaries. From the Chickasawan or Lignitic Harris has described L. (Alantelluiz) osarkana, from Ozark, Alabama (Bull. Pal., ix., p. 43, pl. 6, fig. 12, 1897). Gabb has described a Lima multiradiata from the California Eocene, between the Tejon and Martinez groups at Lower Lake, Lake County (Pal. Cal., ii., p. 261, pl. 33, fig. 101, 1868), which Cooper also reports from Santiago Cafion, Santa Anna Mountains, Los Angeles County. From the Miocene of Costa Rica Gabb described (Journ. Acad. Nat. Sci. Phila., 2d. Ser., viii., p. 348, pl. 45, fig. 26, 1875) L. (Mantellum) papyracea, and Cooper cites the recent L. (WWantellum) dehiscens Conrad, from the Pliocene of Santa Barbara, California. Superfamily ANOMIACEA. Famiry ANOMIIDA. In Lphippium sella Gmel., while the nepionic shell is doubtless (as in Anomia) essentially symmetrical and without any byssal notch or foramen, it very early initiates one, with a distinct plug, and then again discards it, so that in the adolescent or adult shell the traces of the process are frequently obliterated. We have in this case the singularity of a shell taking on a very radical modification and then reverting to what is, in the main, its earlier con- TRANSACTIONS OF WAGNER 779 Paes Ae TERTIARY FAUNA OF FLORIDA dition. The hinge-margin in Aphzppium is usually much worn and has lost its original characters, but sometimes we find them preserved. They com- prise an umbonal area covered with a thin ligamentary tissue and presenting, under the umbo, an elevated subtriangular swelling recalling the deltidium in some Brachiopods. The inner margins of the cardinal border in the right valve are, as it were, detached, except at the umbonal end, and bent down- ward into the cavity of the shell, carrying with them on their external edges a portion of the ligament which, like the shelly crests upon which it is seated, still remains continuous with the original ligament and cardinal border under the umbo, though in the opposite (left or convex) valve it is mainly accom- modated in a pair of grooves corresponding to the crests. In addition to this, the ligament sezso stvicto, there is also a small and feeble resilium situated in the angle between the divaricating crests. Whether this is caused by an advance with the growth of the shell of the external ligament over the angle formed by the crests under the umbones, or is an original structure, the material at my disposal is insufficient to decide. At all events, the sinus and subsequent perforation is situated anteriorly to the anterior of the two chon- drophores, or crests, as, according to the anatomical structure, is inevitable. In Placenta (P. placenta L.), however, we have a different state of things. Here the cardinal margin is so narrow that the external ligament, if any, has disappeared at an early age, leaving the two unequal chondrophores more nearly parallel than occurs in /phzppeu7 and not united in an angle at their upper ends. The anterior cardinal margin is compressed into a narrow wing with a groove for a byssus, as in some species of Pecten. The groove has its edges reflected and thickened, and in most cabinet specimens, unless eroded, is represented externally by a thread-like elevated ray. Pododesmus Philippi (Wiegm. Arch., 1837, p. 385) was founded on Placi- nanomia rudis Brod. from Cuba, a species which differs from JZomia Gray in having a small, solidly soldered-up byssal foramen and a single muscular impression (fide Philippi); the latter character would be true if the impres- sion were regarded as additional to the byssal scar, but it is probable that Philippi took the latter for the adductor scar and did not see the true muscu- lar impression at all. However, it is likely that Joma, at best, can form no more than a section of Pododesmus, which is long prior to Gray’s subgenus. From Carolia to Pododesmus is a short step; another step, somewhat shorter, brings us to Moma, The genus Placunanonua Broderip was founded on a remarkable and still FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA ei very rare shell, the P. Czmingu of west Central America. It is, in some respects, intermediate between “p/ippium and Monta Gray, but presents additional characteristics of its own. The shell is strongly plicated with a few folds; is attached when very young, but may be free in the adult state. In the right valve the cardinal margin is broad and strongly rugose with interlocking rugosities of both valves. Though deep, they are too irregular in form to be called teeth. In the right valve two strong elevated crests—the auricular crura—meet above at a very acute angle, and are received into sockets in the opposite valve, separated by a space bearing a strong median ridge. The ligament connects the outside of the crests with the sockets, but is continuous with a resilium occupying the upper third of the space between the crests. The adductor leaves a large subcentral, nearly circular, impression on both valves. The byssal foramen is closed at an early age, leaving a round scar between that of the adductor and the end of the anterior crest, which scar is joined to the beak by a linear, solidly cemented suture. The byssal muscle persists as an accessory adductor in function. There is no perforation of the shell nor any necessary connection with external objects, in the adult state, any more than in Epluppium or Carolia. None of the other genera of the group exhibit the interlocking rugose cardinal area. The species by which the genus Placunanomia is usually judged belong to a group, properly separated by Gray in 1849 (P. Z.S., p. 121) under the name of Monza, with P. macroschisma Deshayes as the type. In Moma there is a very large, partly shelly, partly corneous, byssal plug, embraced by the right valve (but with the suture always unsoldered, though close fitting), by which the animal is attached at all stages of its existence, unless in the larval condition. There is no cardinal area, no interlocking teeth or rugosities, or paired, elevated internal crests or median internal resilium connecting the valves below the chondrophoric arch. In Monta macroschisma as compared with Placenta we have a condition more like that of Aphzppim, but with a large notch and byssal plug, while the chondrophoric margin is arched and not angulated, being represented by a single pedunculated wide mass with a resilium under the arch. That por- tion of the ligament attached to the chondrophore has become so large and massive that it has supplanted entirely the remnant on the cardinal margin, and the latter, at least in adults, is non-existent. In the left valve the margins of the ligamentary scar are sometimes moderately thickened, but the process 14 TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA NI MI iS) has not been carried so far as to form crura. Coincidently with the existence of the enormous plug in this group, the byssal muscle has been enlarged until it exceeds in section the size of the adductor, above which it is inserted on the surface of the left valve. In Avomea proper and Anxzgma, the other features not being greatly modified, we have the byssal muscle divided into several bundles, each producing its separate scar on the upper valve. In the form of Carola, which we are about to describe, we have combined with the single chondrophore of JMJonza the obsolescent notch and plug, to- gether with the simple adductor scar of Aphzppium. The sensible but narrow cardinal area of the latter is represented by a broad and conspicuous margin. The lateral edges of the ligamentary scar in the left valve form narrow elevated crura, while the exterior is free from the radiating striae common to all the other forms and resembles that of the smooth Anomias. If these differences be taken as sufficient for establishing a section of the subgenus, the name Wakullina will be used, from Wakulla County, Florida, in which the type specimens were collected. The synonymy of this group is in an unsatisfactory condition. The genus Placenta was first named by Da Costa in his Conchology (p. 271, 1776), though, unfortunately, this author not having consistently adopted in this work the Linnean nomenclature, it is not entitled to be cited in synonymy. The name Placenta had been used by Klein in 1734 to designate an Echino- derm, but this author is absolutely without a binomial nomenclature and not entitled to any consideration in discussing systematic questions. Da Costa’s name became current among students and was adopted in proper binomial form by Retzius in his well-known dissertation on new genera of shells, pub- lished by his pupil, Phillipson, at Lund in 1788. Meanwhile Linné had referred the species to Avomua under the name of Anonia placenta, Yn an unpublished description of the shells in the ducal cabinet of Portland, Dr. Solander had proposed the name /lacuna for the same type, and this was used by Bruguiére on the plates of the unfinished Encyc. Méthodique (174, 175, 1792), though with the genuine Placuna he united certain species of Plcatula. Solander’s name was also quoted by Humphrey in his Catalogue of the Museum of Calonne (p. 45, 1797), which contained a number of specimens derived from the Portland cabinet. A year or two later Bolten revived the hitherto nonbinomial name of Ep/appium employed by Chemnitz to designate (Conch. Cab., viii., p. 116, 1785) the saddle-oyster,—he included that as well as Anomia placenta in his genus FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA (Mus. Boltenianum, p. 166, 1798),—while in 1799 Lamarck (Prodrome, p. 82) adopted Solander’s name with the original type. In 1817 Schumacher used Retzius’s name and correctly placed lacuna in its synonymy. Since that time, however, as was natural, the name adopted by Lamarck has had the wider currency, perhaps partly on account of the erroneous statement by Herrmannsen (Ind. Gen. Mal., i1., p. 277) that Chemnitz refers to Solander’s manuscript name in the volume of the Conchylien Cabinet published in 1785, three years before Retzius gave Da Costa’s name a binomial standing. A careful search of Chemnitz in the place indicated shows no reference what- ever to Solander or his name, as has already been pointed out by Deshayes. In 1848 Gray enumerated the species of Placenta Retz. (P. Z. S., 1848, p. 114) and divided the genus into two sections or subgenera, 1, Placenta s. s., typified by P. placenta Lin., and 2, Ephippium (Chemn.), after Bolten (++ Sed- lavia Link, 1807), comprising the saddle-oysters. The name Lphippiun (Bolten) antedates by four years its use in Entomology, even if we do not go back to the non-binomial Chemnitz, and though part of the species were referable to Placenta Retz., the remainder, belonging to an unnamed group, were entitled to retain Bolten’s name. If Bolten’s name had been entirely new the absence of a diagnosis might militate against its acceptance, but as it is really a revival of a well-known but not binomially established name, with proper references to Chemnitz’s and other figures and to Gmelin’s syn- onymes, while there can be no possible doubt as to the species included, it would seem that no question need arise on this account. In 1864 Deshayes referred a problematical fossil (Placuna solida Desh.) to this group under the name of Hemzplicatula, for which in 1886 Fischer proposed the emended form of Sesziplicatila. Its true relations can only be determined by a more critical examination than it seems yet to have received. In 1867 Conrad described a genus Paranomia, from the Ripley group (Upper Cretaceous) of Alabama, to which he referred his Placunanomia Safford: (Journ. Acad. Nat. Sci, 2d Ser., iv., p. 290, pl. 46, fig. 21) and the Placuna scabra of Morton. The typical species is ill preserved, and the beaks almost always wanting, but, from the examination of a large number of speci- mens, it seems probable that the genus resembles J/owza in its external char- acters; the presence of a triangular chondrophore recalls Azoma, but there is not sufficient evidence of a permanent foramen, the muscular impressions are not preserved, and there is in the right valve, associated with the single chondrophore, a pair of low, narrow crests, recalling those of Placenta, but TRANSACTIONS OF WAGNER 774 TERTIARY FAUNA OF FLORIDA obviously of different function. The genus is a puzzle and cannot as yet be safely united with any other. Dzploschiza Conrad, however, appears to be founded on a broken valve of an ordinary Axoma. It is impracticable to attempt here a revision or discussion of the names which have been applied to exotic fossils apparently related to this group, as the material is wanting, and few of them have been intelligently studied in the light of the anatomical relations of the recent forms. In 1870 Stoliczka (Cret. Pelec. India, p. 451), misled by an imperfect knowledge of its synonymic status, proposed for Ephzppium (Bolt.) Gray the name Placunema, which falls into synonymy. It seems to the writer that the absence of any foramen and the perma- nently byssiferous habit of //acenta generically distinguish it from all the foraminiferous Axomede. Its arenaceous habitat is also different from all the rest. Placunanomia as typified by P. Cumingit seems also a good genus. The list, omitting doubtful forms and unstudied exotics, will stand about as follows: 1. Byssal scars absent or obsolete. Genus Placenta. Type P. orbicularis Retzius. Genus Ephippium. Type £. sella Gmelin. Genus Carolia. Type C. placunoides Cantraine. Section Wakullina. Type C. floridana Dall. to . A single conspicuous byssal scar on the disk. A. Adult foramen closed; hinge armate. Genus Placunanomia. Type P. Cumingu Broderip. B. Adult foramen small; hinge unarmed. Genus Pododesmus. Type P. rudis Broderip. C. Adult foramen large; hinge unarmed. Section Monta. Type P. macroschisma Deshayes. . Two byssal scars on the disk; hinge unarmed; foramen open. 7 LoS) A. Main byssal scar largest; foramen ample. Genus Anomia. Type A. ephippium Linné. B. Adductor scar larger than those of the byssus ; foramen small. ? Section Patro. Type A. elyros Gray. C. Main byssal scar distant from the two others. Section Aizgma. Type A. enigmatica Jonas. FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA 775 In addition to the major and minor byssal scars on the disk, there is a small semilunar scar near the resiliary pit, due to a branch of the byssal muscular system. The “lacuna papyracea,’ of which the nepionic foramen is figured by Fischer (Man. Conch., p. 953, fig. 701), belongs to the genus Ephippium. The dynamic relation between the size and position of the byssal foramen and the byssal scars is sufficiently obvious. The only American fossil referred to Placuna,—P. scabra Morton,—as already indicated, belongs to the Cretaceous, and is placed by Conrad in his genus Paranomia. Genus CAROLIA Cantraine. Carolia Cantraine, Bull. Acad. Sci. Brux., 1838, p. 111. Type C. placunotdes Cantraine ; Fischer, J. de Conchyl., xxvili., p. 345, pl. xil., 1880; Man., p. 932, fig. 700, pl. xvi., fig. 7, 1886. Lower Eocene of Egypt. Hemiplacuna (Sby. MS.) Gray, P. Z. S., 1849, p. 123. Type A. Roztevi Sby. Cf. Roziére in Descr. de Egypte, Mineralogie, pl. xi., fig. 6. Shell thin, nacreous, with radiating striz, the right valve flattened; resilium rounded-triangular, internal, large, attached in the right valve to a pedunculate chondrophore seated on the anal side of the umbo and extended adorally so as to bring the middle of the resilium in the median line of the valve; in the left valve the resilium is attached in the cavity of the umbo, leaving a broad, fan-shaped, thickened scar of attachment, of which the anterior and posterior margins are elevated into diverging lamellz. In the young stage the right valve is perforate for the passage of a byssus or byssal plug, which gradually atrophies, so that in the full-grown shell the sinus and perforation are closed with shelly matter and so overshadowed by the heavy chondrophore as to be hardly perceptible even as a scar. It should be observed that the attachment of the resilium is wholly posterior, and not the result of the merging of an anterior and posterior chondrophore. The scar of the adductor in each valve is single, orbicular, and nearly central, with two very minute accessory pedal or byssal muscular scars above it in the left valve. This genus has been discussed by Gray and Fischer, the latter giving some instructive figures of the gradual obliteration of the sinus and of the analogous early sinus in Ephippium papyraceum. For a fine specimen of the Carola figured by Roziére in Savigny’s Egypte I am indebted to Lieutenant S. M. Ackley, U. S. N., who obtained it from the Eocene Tertiary bed underlying the desert, about five miles west from the bed of the ancient Lake Meeris, in the Fayoum. It measures thir- TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA NI NI (>) teen by fifteen centimetres, being somewhat wider than high. The chondro- phore is almost sessile, so short is the peduncle; the scar of the byssal foramen is very distinct, about two millimetres in diameter and ten millimetres below the base of the chondrophore. So small is the play of the valves that the cardinal border, senso stricto, has ceased to exist, and the convex valve has that margin flattened and produced dorsally, taking on a patelliform character. The elevated lateral margins of the ligamentary scar are clearly of dynamic origin and not developed crura, A singular fact is that the convex valve retains several of the sessile plugs of a large Anomea and adherent portions of their valves. This species has no cardinal area, the surface is radiately striate and of that talcose aspect proper to Placenta and Ephippium,; the distal portion of the chondrophore bears traces of a reflexed lamina like that we figure for our Floridian form (pl. 24, fig. 60). This character again is obviously dynamic, and is probably absent in young and perhaps some adult specimens. Carolia (Carolia) jamaicensis n. s. PLATE 33, FIGURE 21. Eocene (?) of the Cambridge beds, Cambridge, Jamaica; R. T. Hill. Shell of moderate size and irregular growth, extremely compressed, thin, normally suborbicular; upper valve slightly convex, with inconspicuous beak and no clearly defined cardinal area; surface of both valves covered with fine, vermicular, close-set radial stria and threads; lower valve flat, the fora- men indicated by a small tubercle which in the course of growth comes to lie almost directly under the wide, little-elevated chondrophore; adductor scar subcentral, rounded; shell silvery, subnacreous. Alt. of portion figured (broken) 40, lat. 47, diam. 5 mm. These shells were found mixed in with the remains of Larretta and Rudistes of several species which appear to be standing in the limestone in the position in which they grew, in what Professor Hill calls the Cambridge formation and refers to the Upper Cretaceous. Considering the relations of the genus, I cannot regard the Carola as Cretaceous, and prefer to look at it as either a subsequent deposition, or as possibly having grown upon previously fossilized Cretaceous Rudistes upon which an Eocene sea had encroached. This view is supported by the presence of other fossils of unmistakably Eocene facies in the limestone in which the Carolia occurs. FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA N NI Sy Carolia (Wakullina) floridana Dall. PLATE 24, Ficures 5, 6, 64, 7, 7 2. C. (Wakullina) floridana Dall, Proc. U. S. Nat. Mus., xviil., p. 21, 1895. From the Oligocene of Florida in the Sopchoppy limestone on the banks of Deep Creek near the Sopchoppy River, Section 13, Township 4, Range 3, Wakulla County, Florida; collected by L. C. Johnson, of the United States Geological Survey; also in the “ Fuller's earth” bed by Dr. D. T. Day, at Quincy, Florida. Shell thin, not sculptured, nacreous, suborbicular, and adherent, some- what irregular; tight valve flattened or concave, especially at the umbo ; left valve convex with a moderately prominent umbo near the cardinal margin ; hinge-margin variable, but always with a transverse flattish area arched in the middle over the attachment of the internal ligament; exterior irregularly im- bricated by the scaly nacreous layers; interior smooth, with a large subcentral nearly orbicular adductor scar; right valve with the minute sealed byssal foramen under the-middle of the chondrophore connected by a soldered linear suture with the upper anterior margin of the valve; chondrophore rounded triangular, broad, radiately rugose above, recurved as a thin lamina from the umbo in fully adult specimens (see figure), rather closely sessile and fitting into the umbonal cavity of the opposite or convex valve; left valve with the ligamentary attachment broadly triangular, marginated by a thin lamellar deposit of shell substance on each side and arched over by the elevated portion of the cardinal area. There is no trace of a scar correspond- ing to the byssal muscle of youth in adult specimens. Antero-posterior diameter 110, dorso-ventral height 110, maximum thickness of the closed valves 9 mm. This fine shell, curiously enough, is, so far as known, the only species in the Sopchoppy limestone which retains its shell-structure, all the other mollusks, so far as observed, being represented only by their impressions in the soft limestone. It is interesting to find an Egyptian type in our southern fauna, though the only relation between them is, in the writer’s opinion, that which both bear to the Azomde which preceded them, and the analogous recent forms which have succeeded to them. The characters upon which Carolia is based are purely dynamic and might be expected to occur in a long succession of Axomde of any region, the several Carolias having no genetic connection with each other, as such, any more than the Oregonian Bazzssa has with those of other continents now living. TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA “I a I (oe) Genus PLACUNANOMIA Broderip. Placunanomia Brod., P. Z. S., 1832, p. 28. Type P. Cumingit Brod. Placunomzia Swainson, Malac., p. 390, 1840; Gray., P. Z. S., 1849, p. 120. Placunanomia plicata Tuomey and Holmes. P. plicata T. and H., Pleioc. Fos. S. Car., p. 19, pl. 6, figs. 4-6, 1855. Newer Miocene of Duplin County, North Carolina, at the Natural Well, Burns; and at Smith’s on Goose Creek, South Carolina, Tuomey and Holmes ; living in Charleston Harbor, South Carolina? Ravenel. Tuomey and Holmes state that Dr. Ravenel had in his collection a recent specimen of this species obtained from Charleston Harbor, but the absence of any confirmatory evidence for more than forty years leaves the accuracy of this determination in doubt. The fossil much resembles P. Cumingii, but is less deeply plicated, more delicate, with the rugosities of the cardinal border more feeble, and the byssal scar nearly equal in size to that of the adductor, in the right valve, while in P. Czamingi.the adductor scar is conspicuously the larger of the two. If the present species be extinct, as seems likely, it is one of several instances where peculiar forms which were common to both coasts of America before the Pliocene survive the separation of the two oceans only on the Pacific side, a result which I believe to be due to the much steeper slope of the Pacific shores, which enabled many species of mollusks or their embryos to migrate seaward as the land rose and thus survive the change, while the more level margin of the Atlantic resulted in the total desiccation of a wide strip of sea-bottom in a relatively short space of time, thus exterminating a large proportion of the less active littoral fauna simultaneously over the whole of the elevated border of the coast. Conrad has briefly described (Kerr, Geol. Rep. N. Car., App., p. 19, 1875) an unfigured Miocene species from North Carolina under the name of P. fragosa. The type is lost and the generic place of the species is doubtful. Placunanomia lithobleta n. s. Rare in the Oligocene of Bowden, Jamaica; Henderson and Simpson. Shell resembling P. plicata, but flatter; not plicate, but gently waved distally ; surface radially sculptured with minute, almost microscopic, threads, which are frequently interrupted, whén the termination of the proximal part of the thread is swollen, resembling a minute head or pustule; interior re- sembling P. plica/a, but the hinge weaker, the amorphous irregularities con- FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA 779 fined to a very small space near the umbo, and inconspicuous ; crura of the lower valve small, forming an acute angle, well elevated, the socket for their recep- tion on the opposite valve shallow. Alt. about 50, lat. 50, diam. about 8 mm. This form is distinguishable at once from the Pliocene and recent species by its peculiar surface sculpture. Genus PODODESMUS Philippi. Pododesmus Phil., Wiegm. Archiv., i., p. 385, 1837; Handb. der Conch., p. 380, 1853. Type P. decipiens Phil. = P. rudis Brod. 2 Tedinia Gray, P. Z.S., 1851, p. 197; Cpr., Maz. Cat., p. 165, 1857. Placunanomia pars, Broderip, Gray, Carpenter, Reeve, eZ a/. Pododesmus rudis Broderip. Placunanomia rudis Brod., P. Z. S., 1834, p. 2; Reeve, Conch. Icon., pl. 1, fig. 2, 1859. Pododesmus decipiens Phil., Wiegm. Archiv., i., p. 387, pl. 9, fig. 1, 1837. Placunanomia echinata Brod., 7. c.,;; Reeve, Conch. Icon., pl. 1, fig. 1, 1859. Placunanomia abnormatis Gray, P. Z. S., 1849, p. 121; Reeve, Conch. Icon., pl. 3, fig. 14.a-0. Placunanomia (Pododesmus) rudis Gray, P. Z. S., 1849, p. 120. Placunanomia Flarfordi Reeve, Conch. Icon., pl. 2, figs. 8a, 88, 1859. ? Placunanomia Gould Reeve, op. cit., pl. 3, fig. 10 a, 6, 1859. ? Chipola Oligocene of the Chipola River, Florida; Dall. Recent from Cedar Keys, Florida, through the West Indies, and south to the mouth of the La Plata River, South America. This shell resembles Axoma aculeata externally, from which it is dis- tinguished by its small, often obsolete, byssal foramen, and by having only two muscular impressions,—one large and conspicuous, which is the mark of the modified byssal muscle, and another below it, smaller and hardly distin- guishable on a fresh polished specimen, which is due to the adductor. It is likely that the Chipola species is distinct and could be properly characterized when adult, but the two upper valves obtained are quite young, and offer absolutely no characters by which they can be differentiated from P. rudis of the same size. I have therefore thought it best to refer the form to P. rudis until more material is available. The relative position of the scars in the Anomude changes with age. Pododesmus scopelus n. s. PLATE 30, FiGuRE 8. Uppermost Oligocene of the Alum Bluff beds, at Rock Bluff, Chatta- hoochee River, Florida; Dall. TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA “I oe) e) Shell large, irregular, taking the form of the object to which it adheres, the upper valve convex, with rude, irregular radial threads or unequal riblets, close-set and frequently broken up so as to appear vermicular; interior smooth, with two muscular impressions rather feebly impressed, the site of the resilium deeply impressed and extending behind the cardinal margin; attached valve concave, irregular, the foramen small and elongate, probably eventually closed, the chondrophore projecting partly over it in our specimens ; space between the valves very small. Alt. 44, lat. 58, diam. 7 mm. This species is one of the few characteristic fossils which are preserved at Rock Bluff, and has not occurred at Oak Grove or Alum Bluff in the same horizon, which may be explained by the fact that the bed at Rock Bluff is an old oyster reef, in which only Ostrea, Turritella, the present species, and frag- ments of Pecten and Lalanus are preserved. The matrix is ill adapted to conserve fossils in their perfection, and the specimens of Pododesmus are very irregular and mostly shattered by internal movements of the marl. Section JMJonia Gray. Pododesmus (Monia) macroschisma Deshayes. Anomta macroschisma Desh., Rev. Zool. Soc. Cuvierienne, p. 359, 1839; Mag. Zool., 1841, pl. 34; Middendorf, Beitr. Mal. Ross., iii., p. 6, 1849; Phil., Abbild. beschr. Conch., p. 132, pl. 1, fig. 4, 1850. Placunanomia macroschisma Gray, P. Z. S., 1849, p. 121; Cat. Anom. Brit. Mus., p. 12, 1850; Cpr., Rep. Brit. As., 1863, p. 646: Placunanomia cepio Gray, P. Z.5., 1849, p. 121; Cat. Anom. Brit. Mus., p. 11, 1850; Reeve, Conch. Icon., pl. 3, fig. 12, 1859. Placunanomia alope Gray, op. cit., p. 122, 1849; Reeve, Conch. Icon., pl. 3, fig. 11. Upper Miocene of Sooke, Vancouver Island, C. F. Newcombe; Plio- cene of San Diego, California, Hemphill; Pleistocene of California, Oregon, and Alaska, Dall; recent from North Japan to Kamchatka, the Aleutian district and southeastern Alaskan coasts south to Lower California in shallow water. This species is abundant in the Pleistocene and occurs in the Californian Pliocene of the San Diego well. It is a very large, solid, and characteristic species. Carpenter referred a fossil of the Carrizo Creek Miocene, Anxomia subcostata, to this species, but the swdcostata is a true Anomia. It is possible that Placunanomia tnornata Gabb, referred by him to the Cretaceous and by Conrad to the Tejon Eocene, may belong in this section, and it even greatly resembles this species externally (cf. Pal. Cal., p. 217, pl. 32, figs. 288, 288 a, FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA NI (ee) = 1868). Placunanonua fragosa Conrad, from North Carolina, from the descrip- tion may be referred to this group, but in the absence of any type or figure, or even any exact locality for the species, it is impossible to be certain. An unnamed species of the Chickasawan (Harris, Bull. Pal. No. 9, p. 42, pl. 6, fig. 10), if the scars are completely figured, should belong in this group. Genus ANOMIA (Linné) Miller. Anomia (pars) Linné, Syst. Nat., Ed. x., p. 700, 1758. Anomia Miller, Prodr. Zool. Dan., pp. xxx., 248, 1776; Retzius, Diss., p. 9, 1788. Echion +- Echionoderma Poli, Test. Utr. Sicil., i., p. 34, and il., p. 255, 1791. Cefa (Hwass) Humphrey, Mus. Calon., p. 45, 1797. fenestela Bolten, Mus. Boltenianum, p. 193, 1798; Ed. ii., p. 134, 1819. Anomya Agassiz, Moules des Moll., 1., p. 23, 1839. Diploschiza Conrad, Am. Journ. Conch., il., pp. 77, 105, 1866. Not Avomza Da Costa, Elem. Conch., p. 292, pl. vi., figs. 3, 10, 1776; nor of Bolten, Mus. Bolt., p. 134, 1798 (Brachiopoda). The fossil species of this group are very difficult things to study, since the lower valve is seldom preserved and the muscular impressions can seldom be made out. I shall therefore refrain from consolidating doubtful species in the absence of a sufficiency of material for thorough study. To the natural difficulties is added that due to the fact that the sculpture in this genus is very variable in perfectly normal specimens and is further complicated by the differences of form and surface due to the object upon which they are sessile. I have satisfied myself by the examination of a large number of recent speci- mens belonging to a single species from a single locality that the relative positions of the adductor and byssal scars on the left valve are not constant in the same individual at all ages, and consequently that small differences of this kind cannot safely be used as specific distinctions. The best character seems to be the more minute surface sculpture when fully developed in normal specimens. Anomia lisbonensis Aldrich. Anomia ephippioides Gabb, var. “sbonensis Aldr., Bull. Geol. Surv. Ala., i., p. 41, pl. 4, fig. 6, 1886. Claibornian Eocene at Lisbon Bluff, Alabama, Aldrich; and in similar horizons in Webster and Bienville Parishes and near Nachitoches and Mt. Lebanon in Louisiana, Vaughan; near Wheelock and in Lee County, Texas, Singley and Johnson. This is a normally smooth, large species, with radiating bands of color on TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA a lighter ground. It is clearly distinct from the species to which it was originally referred as a variety. Anomia ephippioides Gabb. Anomia cphippioides Gabb, Journ. Acad. Nat. Sci. Phila., 2d Ser., iv., p. 388, pl. 67, fig. 59, 1860. Claibornian Eocene of Texas, Gabb; near Laredo and Wheelock, Texas, Johnson and Singley. This species was originally very imperfectly described and figured from worn specimens. The chief specific character is not alluded to. The young when in perfect condition are covered with minute pustules; as the shell approaches maturity these elongate and become close-set, rather coarse threads, separated by narrower grooves. In perfect condition it cannot be mistaken for any other American species. This sculpture, it should be clearly understood, is normal to the species and entirely independent of irregularities due to sztzs. Anomia Ruffini Conrad. Anomia Ruffint Conr., Proc. Acad. Nat. Sci. Phila., i., p. 323, 1843; Medial Tert. Fos., p- 74, pl. 42, fig. 6, 1845 ; S. I. Checkl. Eoc. Fos., p. 3, 1866. Anomia McGeet Clark, Bull. U. S. Geol. Surv., No. 141, p. 86, pl. 34, fig. 5 a—-d, 1895. Eocene, Waterloo, Pamunkey River, New Kent County, Virginia, E. Ruffin; Hanover County, Virginia, and various localities in Maryland, Clark and Whitfield. (Miocene of ?) Specimens collected by Ruffin, in the National Museum, from Shell Bank and Waterloo, leave little doubt that Clark’s species, from the same region, is identical with that of Conrad. The characteristics of the species are its large size and the irregular fluting of the shell, especially near the margins. The muscular scars are usually difficult to make out, but the species is an Azomia and not a Pododesmus, as might be suspected from Clark’s figure. The species is not found in the Caloosahatchie beds, though included by an error of identification in Heilprin’s list. The other Eocene species referred to in the literature, but which I have not identified, are Axomza jugosa Conrad (Proc. Acad. Nat. Sci. Phila., i., p. 310, 1843; ili., p. 22, pl. 1, fig. 15) from the Jacksonian of South Carolina,— a species of which neither the description nor the figure affords sufficient information to enable one to identify it—and A. navicelloites Aldrich (Nautilus, xi., p. 97, Jan., 1898) from the Wood’s Bluff horizon at Choctaw Corner, Alabama, which is still unfigured. FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA Anomia microgrammata n. s. PLATE 35, FIGURE IT. Oligocene of the Chipola beds at the Chipola River and the lower bed at Alum Bluff, Florida; also at Ballast Point, Tampa Bay, Dall, Burns, and Willcox; and at Bowden, Jamaica, Henderson and Simpson. Shell small, irregular, characterized by a fine, almost microscopic, close- set radial striation covering the whole surface and flaring away from the medial line of the valve in a somewhat wavy manner; the two lower scars on the left valve are subequal and side by side, the major byssal scar larger, oppo- site the medial line between them; the beak of the left valve is some distance within the margin, and the surface where worn appears smooth; the striation is only visible under a lens in most cases. Alt. 17, lat. 25 mm. This species is recognizable by its fine, almost divaricate striation, which does not break into pustules near the beaks, as in the larger and more coarsely sculptured A. ephippioides. The specimens from Bowden have a still finer and often partially obsolete striation. They form the variety zdeczsa (Guppy, MS.). Anomia floridana n. s. PLATE 35, FIGURE 7. Oligocene of Oak Grove, Santa Rosa County, Florida; Burns. Shell of moderate size, usually rather convex, the surface irregular, obso- letely microscopically radially striated, more or less irregularly feebly pustular and with obsolete, broken, feeble radial plications; the minor byssal scar is above and slightly further back (about half its own width) than the adductor scar of the same size; the major byssal scar is rounded and much larger, situated directly above the minor one, so that the three scars are nearly in one dorso-ventral line; the beak of the left valve is at the cardinal margin. Alt. of largest specimen 35, lat. 39 mm. This species is intermediate in size and character between A. mcrogram- mata Wall and A. Ruffint Conrad. It is smaller and less sculptured than the latter, which also wants the microscopic striation; it is larger, less sharply striated, and has the beak and scars situated differently from the former. Many of the specimens still retain some of the original greenish coloration. The only other Oligocene species described from the North American and Antillean regions is the A. wmbonata Guppy, from Trinidad (Proc. U.S. Nat. Mus., xix., No. 1110, p. 235, pl. 30, fig. 6, 1896), which is small, with minute pustulation but no radial striation. TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA 784 Anomia simplex Orbigny. Anomia ephippium Conrad, Medial Tert. Fos., p. 75, pl. 43, fig. 4, 1845. Anomia simplex Orb., Moll. Cubana, ii., p. 367, pl. 38, figs. 31-3 (1845, Spanish edition), 1853; Dall, Bull. U. S. Nat. Mus., No. 37, p. 32, pl. 53, figs. 1, 2, 1889. Anomia acontes Gray, P. Z. S., 1849, p. 116. Anomia Conradi Orb., Prodr. Pal., ili., p. 134, pl. 25, fig. 30, 1852; Conrad, Proc. Acad. Nat. Sci. Phila. for 1862, p. 582, 1863. Anomia ephippium Tuomey and Holmes, Pleioc. Fos. S. Car., p. 18, pl. 5, fig. 4, 1855 ; Holmes, P.-Pl. Fos. S. Car., p. 11, pl. 2, fig. 11, 1858; Emmons, Geol. N. Car., p- 277, 1858; Gabb, Journ. Acad. Nat. Sci. Phila., 2d Ser., viii., p. 380, 1881. Anomia glabra Vervill, Am. Journ. Sci., 3d Ser., iil., p. 213, 1872; x., p. 372, 1875. Anomia electrica Gould, Inv. Mass., p. 140, 1841 ; Binney’s Gould, p. 205, fig. 499, 1870; not of Linné. Anomia squamula Gould, Inv. Mass., p. 140, 1841; Binney’s Gould, p. 206 (young), 1870; non Linné. Anomia Ruffint Heilprin, Trans. Wagner Inst., i., p. 102, 1887 ; not of Conrad. 2 Anomia ephippium Gabb, Geol. St. Domingo, p. 257, 1873. ? Oligocene of St. Domingo, Gabb; Upper Miocene of Duplin County, North Carolina, at the Natural Well, Conrad; of York and Nansemond Rivers, Virginia, Burns; Pliocene of the Waccamaw beds, South Carolina, Tuomey and Johnson; of the Caloosahatchie beds, Florida, Dall; of Limon, Costa Rica, Gabb; Pleistocene of the Atlantic and Gulf coasts from the Carolinas southward, Holmes and Burns; recent from Cape Sable, Nova Scotia, southward to Martinique. I am unable to find any distinctive characters separating the Upper Mio- cene from the recent shells. The surface is normally smooth, and the varia- tions of position in the scars of the left valve are remarkable. In the young the lower pair of scars are usually equal and side by side; as the shell grows older their positions change, and the minor byssal scar is no longer on the same level with that of the adductor. Shells which by some accident of position are forced to grow in elongated form usually have the scars more strung out and more nearly in a single line than the individuals which maintain a normal suborbicular growth. Anomia aculeata Gmelin. Anomia aculeata Gmelin, Syst. Nat., vi., p. 3346, 1792; Gould, Inv. Mass., p. 139, fig. go, 1841; Binney’s Gould, p. 204, fig. 498, 1870; Verrill, Rep. U. 5. Fish Com. for 1871-2, p. 697, pl. 32, fi gs. 239, 240, 240@, 1873; Dall, Bull. U. S. Nat. Mus., No. 37, p- 32, pl. 53, figs. 5~ 8, 1889. FREE INSTITUTE OF SCIENCE 785 TERTIARY FAUNA OF FLORIDA Upper Miocene of York River, Virginia, Harris; Pleistocene of Sankoty Head, Massachusetts, Verrill; recent from the Arctic Ocean south to Cape Fear, North Carolina, on the Atlantic coast; also on the northern coasts of Europe. The presence of this species in the Virginia Miocene is established by some beautifully preserved small valves with the characteristic sculpture obtained by Mr. Harris. The A. delwmbis Conrad (Proc. Acad. Nat. Sci. Phila. for 1862, p. 582) is a mere list-name, never described or referred to a locality. A well-defined species is the A. swbcostata Conrad, from the Miocene of the Carrizo Creek beds, Colorado Desert, California. (Pac. R. Rk. Reps., v., p. 325, pl. 5, fig. 34, 1855.) It is strongly radially plicated. Anomia limatula Dall. PLATE 35, FIGURE Ig. Anomia limatula Dall, Proc. U. S. Nat. Mus., 1., p. 15, 1878. Pliocene of Ventura County, California, eight miles inland and two hundred feet above the sea level, Bowers; of Coronado beach, San Diego, California, Hemphill; and of Pacific beach, near San Diego, Stearns; Pleistocene of Spanish Bight, Coronado beach, San Diego, and of San Pedro Hill, Los Angeles County, California, Stearns. A fine, large species, which is characterized by its peculiar, finely granulose surface, devoid of all normal radial sculpture, and which still retains on its yellowish valves traces of dark purple, irregularly radial blotches. The cal- careous plug of this species is peculiar, being hollow, and the cylinder incom- plete on one side. From the Pleistocene of San Pedro Hill, California, has been obtained A. lampe Gray, the common Axomia of the recent fauna of the coast (Gabb, Pal. Cal., ii., p. 106, 1868). This is almost invariably radially ribbed and often concentrically grooved, and has a polished surface quite unlike that of A. limatula. It has also been obtained by Stearns at Spanish Bight, Coronado beach, San Diego, California. Superfamily MYTILACEA. Famity MYTILID. Genus MYTILUS (L.) Bolten. < Mytilus Lin., Syst. Nat., Ed. x., p. 704, 1758; Miiller, Zool. Dan. Prodr., p. 249, 1776 ; Da Costa, Brit. Conch., p. 214, 1778; Bruguiére, Encye. Méth., i., xiii., 1789 ; Humphrey, Mus. Calon., pp. 42, 43, 1797. TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA 786 < Mytilus + Volsella Scopoli, Intr. Hist. Nat., pp. 396-7, 1777; Modeer, K. vet. Acad. Handl., xiv., pp. 179, 181, 1793. < Mytulus + Perna Retzius, Dissert., p. 20, 1778. = Mytilus Bolten, Mus. Bolt., p. 157, 1798; Ed. ii., p. 110, 1819. < Mytulus Cuvier, Tabl. Elem., p. 423, 1798. = Mytilus Lamarck, Prodr. Nour. Class. Coq., p. 88, 1799. Type JZ. edulis L.; Link, Beschr. Rostock Samml., p. 158, 1807. ? Arcomytilus Agassiz, 1840. Type Mytelus pectinatus Sby. (2 = Septifer Recluz, 1848). The name JZytilus for the mussels is of very ancient date, and in adopt- ing it for his heterogeneous genus Linné merely followed classical usage. If we ascribe the genus to Linné we are obliged to seek the type by his method of taking the most common species, and while this might be done under stress of circumstances, it is better, if practicable, to follow the regular rule. The naturalists who followed Linné did not grasp the characters which separate the groups of the Linnean Mytili, and after eliminating the fresh- water species, they seemed to fall back on the dentiferous or edentulous char- acter of the hinge in their divisions of the group. Thus Scopoli divided the Linnean Mytilus into an edentulous group, for which he preserved the name without citing any examples, and Vo/se//a, which included species with one or more teeth. It was by some misidentification, therefore, that AZytelus modtolus was included in Scopoli’s Vo/se/la and defined as having one tooth. Modeer followed Scopoli, and Retzius did the same, except that he proposed a genus Ferna for the forms Scopoli had named Volse//a. Even Cuvier included both Mytilus and Modiola in his Mytulus. The first author who seems to have had clear and what may be termed modern views on the subject was Bolten, who divided his dZyizdus into a smooth and a sulcate group and excluded nearly all the species not Mytiloid, as now understood. He did not name a type, but this deficiency was supplied by Lamarck a year later. A consideration of these facts shows that the course of some writers who would substitute Volsella or Perna for Modiolus Lamarck is unwarranted by the history of these names. The quadrinomials of Poli (Cadltriche + Calt- trichoderma, 1791) have no place in our nomenclature. The names which are entitled to adoption are all comparatively modern. The curious twisted sub- genus Sfavelia Gray, which is usually placed with JZytlus, should be removed to Modiolus. Mytilaster Monterosato has vermiculate sculpture. The AZyai occurring in the North American Tertiary are divisible by their sculpture into two sections: FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA Si ioe) N Genus AZytilus (L.) Bolten. Section AZyiilus s.s. Surface with chiefly concentric sculpture or smooth. Type JZ. edulis L. Section Hormomya* Morch (Cat. Yoldi, p. 53, 1853). Shell radially sculptured. Type AZytelus exustus Linné. To these may be added: Subgenus Mytiloconcha Conrad. Apical region of the shell much thickened and produced, with longitudinal grooves. Type MZ. incurva Conrad. The number of species of A7Zyt/us in the Tertiary of the Eastern United States is very small, but the Pacific coast offers a larger number. Mytilus Conradinus Orbigny. Mytilus tncrassatus Conr., Am. Journ. Sci., xli., p. 347, 1841 ; Fos. Medial Tert., p. 74, pl. 42, fig. 4, 1845 ; Tuomey and Holmes, Pleioc. Fos. S. Car., p. 32, pl. 14, figs. 1, 2, 1855; Harris, Bull. Pal., 3, p. 5, 1895 ; not of Deshayes, 1830. Mytilus Conradinus Orbigny, Prodr. Pal., iii., p. 127, 1852. Mytiloconcha incrassata Conr., Proc. Acad. Nat. Sci. Phila. for 1862, p. 291, 1862. Mytiliconcha tncrassata Conr., op. cit., p. 579, 1863. Lower Miocene of Cumberland County, at Shiloh and Jericho, New Jersey, Conrad and Burns; Miocene of the artesian well at Galveston, Texas, between two thousand three hundred and eighty-four and two thousand eight hundred and seventy-one feet below the surface, Singley ; Upper Miocene of the Natural Well, Duplin County, North Carolina, Burns; two and one-half miles below Governor’s Run, Chesapeake Bay, Maryland, Burns; Miocene of South Carolina, in the Darlington District and on the Waccamaw River, Tuomey and Holmes. This species does not differ from the true JZyt/us except in being a little heavier than is usual in this genus. It has not the produced cardinal area of Mytiloconcha, with imperfect specimens of which it has sometimes been con- fused. Mytilus pandionis n. s. PLATE 30, FIGURES 9, Io. Oligocene of White Beach, near Osprey, Little Sarasota Bay, west Florida; Dall. * Arcomytilus Agassiz. (Sowb. Min. Conch., French ed., 1840) is prior in point of time, but the type has the aspect of a Seftifer and the interior is not described or figured. _ 15 TRANSACTIONS OF WAGNER 788 TERTIARY FAUNA OF FLORIDA Shell large, somewhat compressed behind, wide, with the posterior cardinal angle in the anterior third; cardinal line short, an impressed narrow area in front of the beaks nearly half as long as the shell; surface apparently smooth (the type is an internal cast), umbones acute. Alt. 122, lat. 60, diam. 30 mm. This is the only large AZyilus of the JZ. edulis type in the east American Pre-Miocene Tertiary. It somewhat recalls very large specimens of JZ gadlo- provincialis Lam. Mytilus edulis Linné. Mytilus edulis L., Syst. Nat., Ed. x., p. 705, 1758; Dall, Bull. U. S. Nat. Mus., 37, p. 38, pl. 54, fig. 3, pl. 71, fig. 2, 1889. Mytilus boreal’s Lam., An. s. Vert., vi., p. 126, 1819; DeKay, Nat. Hist. N. Y., Moll., p. 182, pl. 13, fig. 222, pl. 24, fig. 256. Mytilus pellucidus Pennant, Brit. Zool., iv., p. 237, pl. 66, fig. 3. Modiola pilex H.C. Lea, Am. Journ. Sci., xlii., p. 107, pl. 1, fig. 3, 1842 (young shell) ; not of Lam., An. s. Vert, vi., p. 112, 1819. Mytilus minganensis Mighels, Proc. Bost. Soc. Nat. Hist., 1., p. 188, 1844. Mytilus notatus DeKay, op. ctt., p. 182, pl. 13, fig. 223, 1843. Pliocene of Great Britain (Red Crag). Post Pliocene of the American coast from Labrador south to St. John’s River, Florida (Verrill), also in northern Europe and on the northwest coast of America; recent from the Arctic Seas south to Fort Macon, North Carolina; Coues. The writer has never observed this species in the Pleistocene of Florida and the Carolinas; the statement of its occurrence there is inserted on the authority of Professor Verrill (Inv. An. Vineyard Sound, p. 693, 1873). Mytilus (Hormomya) exustus Linné. Mytilus exustis L., Syst. Nat., Ed. x., p. 705, 1758; Lam., An. s. Vert., vi., p. 121, 1819? Mytilus bidens L., Syst. Nat., Ed. xii., p. 1157, 1767. Mytilus domingensts Lam., An. s. Vert., vi., p. 121, 1819 ; Orbigny, Moll. Cubana, ii., p- 328, 1845. Mytilus striatulus Schroter, Einl., iii., p. 449, pl. ix., fig. 16. Pliocene of the Caloosahatchie and Shell Creek, Florida, Dall and Will- cox; Pleistocene of Simmons Bluff, South Carolina, Burns; and of the West Indies; recent from Charleston, South Carolina, south to Bahia, Brazil. This well-known species is rare in the marls, and not especially abundant in the Pleistocene. FREE INSTITUTE OF SCIENCE 789 TERTIARY FAUNA OF FLORIDA Mytilus (Hormomya) hamatus Say. ? Mytilus recurvus Raf., Mon. Coq. Biv. Ohio, p. 55, 1820; New Orleans. Mytilus hamatus Say, Journ. Acad. Nat. Sci. Phila., ii., p. 265, 1822; Binney’s reprint of Say, pp- 91, 204, pl. 50; Dall, Bull. U.S. Nat. Mus. No. 37, p. 38, 1889. Brachydontes hamatus Perkins, Proc. Bost. Soc. Nat. Hist., xiii., p. 156, 1869. ? Dretssena recurva Fischer, Journ. de Conchyl., vii., p. 130, 1858. Mytillus striatus Barnes, Am. Journ. Sci., vi., p. 364, 1823 ; Say, Am. Conch., v., pl. 50, Noses Modiola hamatus Verrill, Am. Journ. Sci., 3d Ser., iii., p. 211, pl. 7, fig. 3, 1872; Inv. An. Vineyard Sound, p.“693, 1873. Mytilus carolinensis Conrad, Journ. Acad. Nat. Sci. Phila., vii., p. 244, pl. 20, fig. 6, 1837; Tryon, Am. Mar. Conch., p. 187, fig. 513, 1874. Pliocene of the Caloosahatchie, Dall; Pleistocene of Wailes Bluff, St. Mary’s County, Maryland, Burns; recent from Long Island Sound south to Costa Rica. On the Pacific coast, besides JZ edulis, the Pleistocene affords the great M. californianus Conrad, which even, according to Cooper, is found in the Pliocene, and JZ, pedroanus Conrad, which is perhaps identical with JZ. edulis. The Pliocene affords IZ Middendorfii Grewingk (Beitr. Kenntn. N. W. Kuste Am., p. 360, pl. vii., figs. 3 a—-c, 1850) and JZ, Condoni Dall (Nautilus, iv., p. 87, Dec., 1890), peculiar species with a few broad plications posteriorly, from Alaska and Oregon respectively. In the Miocene are the large JZ Mathew- sont Gabb and the AZ. zmezensis of Conrad, which may prove to be the same as Modiola multiradiata Gabb; both are radiately sculptured and of rather uncertain outline. In the Eocene (Tejon) are JZ ascta Gabb and AT. humerus Conrad, both rather obscure, smooth species, and JZ. (Hormomya) dichotomus Cooper (Bull. Cal. State Mining Bureau, No. 4, p. 49, pl. v., fig. 64, 1894), of which the characters, even the genus, are imperfectly known. Its relations to Septifer dichotomus Gabb and S. bifircatus Reeve, as well as Mytilus bifurcatus (Conr.) Stearns, remain to be clearly made out. Subgenus MYTILOCONCHA Conrad. Myoconcha Conrad, Medial Tert., p. 52, 1840. Mytiloconcha Conrad, Proc. Acad. Nat. Sci. Phila. for 1862, p. 290, 1862. Mytiliconcha Conrad, of. cit., p. 578, 1863. Mytilus (Mytiloconcha) incurvus Conrad. Myoconcha incurva Conrad, Medial Tert., No. 1, p. 3 of cover, 1839; No. 2, p. 52, pl. 28, fig. 1, 1840. TRANSACTIONS OF WAGNER 79° TERTIARY FAUNA OF FLORIDA Mytilus tncurvus Conrad, Proc. Acad. Nat. Sci. Phila., vii., p. 29, 1854. Mytilus (Myoconcha) tncurvus Conrad, Medial Tert., p. 88, 186r. Mytiloconcha incurva Conrad, Proc. Acad. Nat. Sci. Phila. for 1862, p. 291, 1862. Mytiliconcha incurva Conrad, Proc. Acad. Nat. Sci. Phila. for 1862, p. 579, 1863. Mytiloconcha incrassata Whitfield, Mio. Moll. N. J., p. 38, pl. 5, figs. 10, 11, 1894; not of Conrad. Oligocene of Sopchoppy Creek, Wakulla County, Florida, Hodge; Lower Miocene of Cumberland County, New Jersey, at Shiloh and Jericho; of Mary- land, near Skipton, on the Choptank, near Easton, Talbot County, and in Cal- vert County, Harris and Burns; Miocene of South Carolina, Whitfield. The specimens found in New Jersey are very.badly worn and young, hence Professor Whitfield’s identification of them, which I believe erroneous. I have never seen a perfect specimen of this singular shell, but the external casts from the Upper Oligocene of Florida show its characters admirably. The JZ. incrassata Conrad is only a rather heavy JZytdus. The hinge of the present species has two strong teeth in the left and one in the right valve, which are obsolete in senile specimens. These teeth are produced over the cardinal area as ridges, extending to the apex of the valve, with a furrow on each side of each ridge, a single furrow between the two ridges of the left valve. Apart from the furrows and ridges the area is flattened. Close to the posterior margin the groove of the ligament is continued along the edge of the area to the apex. Ina specimen one hundred and twenty millimetres long the area is twenty millimetres long and about the same in greatest width. The characters are those of ordinary MMZytidus, but curiously exaggerated. Mytilus hespertanus Lam., of the Red Crag of Britain, would seem to belong in this group. Genus MODIOLUS Lamarck. Modiolus Lam., Prodr. Nouv. Clas. Coq., p. 87, 1799. Type JZytilus modiolus L. ; Bosc, Hist. Coq., iil., p. 158, 1802; Link, Beschr. Rostock Sammil., lii., p. 146, 1807 ; Cuvier, Regne Anim., ii., p. 471, 1817; Goldfuss, Zool., p. 611, 1820; Risso, Hist., iv., p. 323, 1826; Fleming, Hist. Brit. An., p. 408, 1828; Forbes, Malac. Monensis, p- 43, 1838; Herrmannsen, Ind. Gen. Mal. Suppl., p. 84, 1852. Modiola Lam., Syst. des An. s. Vert., p. 113, 1801. Type 47. papuana Lam. (Encyec. Méth., pl. 219, fig. 1); Roissy, Moll., vi., p. 273, 1805 ; Lam., An. s. Vert., vi., p. 119, 1819; Fischer, Man. de Conch., p. 968, 1886; Dall, Bull. U. S. Nat. Mus., No. 37, Pp: 38, 1889. Amygdalum Megerle, Mag. Ges. Naturf. Fr., v., p. 69, 1811. Type A. dendriticum Meg. (Chemn., xi., p. 198, fig. 2016-7). FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA Brachidontes Swainson, Malac., p. 384, 1840. Type MWodiola sulcata Lam. Modiella Monterosato, Nom. Con. Medit., p. 12, 1884 (not of Hall, 1883). Type Jodiola polita Verrill. Gregariclla Monterosato, of. cz7t., p. 11, 1884. Type ALyttlus petagne Scacchi. Brachydontes Fischer, Man. de Conch., p. 968, 1886; Dall, Bull. U. S. Nat. Mus., No. 37, p- 38, 1889. The main conchological characters which separate this genus from AZytilus are the non-terminal umbones, the tendency to hirsuteness in the epidermis, the absence of developed teeth at the beaks, and the habit of nestling in a mass of byssal fibres with extraneous entangled material which is more or less characteristic of all true J/odioh, though less conspicuous and complete in the larger species. In some deep-water species a real nest is spun, like that of Lima, but more dense. A more efficient protective device could hardly be imagined than the byssal nest of JZ politus, which completely conceals the occupant from predacious marine carnivora. In the matter of sculpture these shells resemble Mytilus, and have a distinct tendency to a medial unsculptured area in the radially sculptured species. Although true teeth are not found in this group, the provinculum is often present and permanent, while its origin is obviously indicated by the secondary denticulations due to the impinging of the radial sculpture upon the margin. I believe hinge-teeth were thus originally initiated, while the secondary denticulations alluded to repeat in the descendants the process by which their remote ancestors acquired an interlocking hinge. The genus Modzolus, like Mytilus, may be divided into natural groups by the sculpture of the surface. Genus Modiolus Lam. Section Modiolus s. s. Surface smooth, shell inflated, edentulous, epi- dermis more or less hirsute. Type JZ modtolus Linné. Section Amygdalum Megerle. Surface smooth, shell compressed, epidermis polished, not hirsute. Type JZ pictus Lam. (Syn. Modiella Mts., not Hall.) Section Gregariella Mts. Surface decussate with a central smooth area ; shell plump, epidermis hirsute. Type JZ petagne Scacchi. (Syn. Botulina Dall, 1889.) Section Lrachydontes Swainson. Surface more or less radially sulcate ; epidermis not hirsute. Type J7 sulcatus Lam. (1819, not 1807). Semi- modiola and Planimodiola Cossmann seem to belong to this section rather than to Modiolaria. TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA Section Botula Morch. Surface deeply concentrically sulcate, shell in- - flated, with conspicuously spiral umbones, the epidermis polished. Type JZ cinnamomeus Lam. This section, if it were not for its peculiar muscular scars, might perhaps equally well be placed under Lithophaga, as has been done by Fischer. It is intermediate, conchologically, between the boring Lzthophagi and the nestlers, as regards externals. Section Arcoperna Conrad (Am. Journ. Conch., i., p. 140, pl. 10, fig. 14, 1865). Shell oval, general form like Lozu/a, but the surface finely striated or reticulated and the margin, except over the ligament, crenulated. Type J/ (A.) filosus Conr., /. c. Jacksonian and Parisian Eocene. This section resembles Modiolaria, except in the absence of the medial unstriated impressed area, and the more oval outline of many of the species. The umbones are swollen and conspicuous. Modiolus cretaceus Conrad. Modiola cretacea Conrad, Trans. Geol. Soc. Penna., 1., p. 340, pl. 13, fig. 2, 1835. Perna cretacea Conrad, Am. Journ. Conch., i., p. 10, 1865. Jacksonian Eocene of Clarke and Choctaw Counties, Alabama, Conrad ; near Fail Post-Office, Alabama, in the Zeuglodon bed, Schuchert; ? Oligo- cene of western Florida, Eldridge; ? Upper Oligocene of Oak Grove, Santa Rosa County, Florida, Burns. This is a large species resembling JZ. modiolus L. A few young shells represented by internal casts and a lot of fragments from Oak Grove, col- lected by Eldridge and Burns, may belong to this species, but are insufficient for a positive decision. Modiolus pugetensis n. s. PLATE 35, FIGURE 17. Eocene of the Puget group in the State of Washington, from the old Renton coal mine, near Seattle; Willis. Shell small, short in front, arched and produced behind; concavely im- pressed in front, with a rounded ridge extending from the beaks to the lower posterior margin; surface polished, with concentric lines of growth. Alt. 17.7, max. lat. 9.5, diam. 5 mm. A larger specimen measures 25 mm. from end to end, but is imperfect. This is a very simple little species, but unlike any other in our Tertiary. FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA NI Ne) ios) Modiolus silicatus n. s. PLATE 27, FIGURE 28. Upper Oligocene of the silex beds at Ballast Point, Tampa Bay, Florida; Willcox and Dall. Shell small, smooth, short, broad, moderately convex, with a few incre- mental striz; beaks low, anterior end very short, posterior margin elevated, rounded, anterior margin slightly impressed; basal end rounded; inner margin smooth, with an unusually deep ligamental sulcus. Alt.e22, max. lat. 16, diam. 9 mm. This is somewhat like the Miocene JZ. znflatus T. and H., but a much smaller shell, with a less impressed lateral area and less sinuous anterior margin. Modiolus inflatus Tuomey and Holmes. Mytilus inflatus T. and H., Pleioc. Fos. S. Car., p. 33, pl. 14, fig. 3, 1855. Perna inflata Conrad, Proc. Acad. Nat. Sci. for 1862, p. 579, 1863. Modiola inflata Whitfield, Mioc. Moll. N. J., p. 39, pl. 6, figs. 3, 4, 1895 (not AZodiola tiflata Whitf., Lam. Rar. Clays, p. 197, pl. 26, figs. 1, 2, 1885). Lower Miocene of Shiloh and Bridgeton, Cumberland County, New Jersey, Burns; Miocene of South Carolina at Giles Bluff, Peedee River, Tuomey. This species is closely related to the recent AZ. tulipus Lam. Modiolus Ducatelii Conrad. Modiola ducatelii Conrad, Medial Tert., p. 53, pl. 28, fig. 2, 1840. Miocene of Calvert Cliffs, Maryland, Professor Ducatel; of Jericho, New Jersey, Burns; of York River, Virginia, Harris; of the Natural Well, Duplin County, North Carolina, Burns. This large species is rather abundant in the Maryland Miocene, but rarely perfect. The JZ gigas Wagner (Trans. Wagner Inst., iv., p. 10, pl. 2, fig. 3, a—b, 1897) differs by its much wider posterior part and attenuated anterior end. It is also Miocene. The other valid species, belonging to the section Modiolus as restricted, found in our Tertiary except JZ. talipus Lam., which occurs in the later rocks of the West Indies, are all Californian and include JZ capax Conrad, Pliocene and Pleistocene (as well as recent); JZ. flabellatus Gld., Pliocene and recent; M. rectus Conrad, Miocene and recent; while the AZ modiolus L., which is said to go back to the Miocene (?) in California, is known from Pleistocene deposits on both sides of the continent as well as the shores of Europe. ‘TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA Modiolus (Brachydontes) grammatus n. s. PLATE 30, FIGURE 2. Oligocene of the silex beds at Ballast Point, Tampa Bay, Florida, Dall; and (var. cwrtulus Dall) of the lower bed at Alum Bluff, Chattahoochee River, Florida, Burns. Shell small, thin, slender, delicately dichotomously radially ribbed ; anterior end extremely short, barely exceeding the beaks; posterior margin angulated; front margin nearly straight, basal end rounded; inner margin delicately crenulate. Alt. 20, max. lat. 8.5, diam. 6.5 mm. This is closely related to the recent JZ. cetrinus Bolt., but is more attenu- ated towards the beaks, and has the dorsal angulation and crenulations of the margin less pronounced. The variety, which more abundant material might show to be a distinct species, is stouter, more triangular, with coarser and more nodulous ribs and stronger crenulations of the margin. Alt. 12, max. lat. 7, diam. 6 mm. e Modiolus (Brachydontes) Guppyi n. s. PLATE 35, FIGURE 16. Oligocene of the Bowden beds, Jamaica; Henderson and Simpson. Shell small, thin, delicate, radiately numerously ribbed, the ribs but seldom dichotomous, general form as in JZ. grammatus, but shorter and more rounded, the surface frequently concentrically faintly undulated, inner dorsal margin sharply crenulate, the rest of the shell margin almost smooth; basal end of valve rounded, dorsal angle obsolete. Alt. 8.5, max. lat. 4.7, diam. 2.5 mm. This differs from the last in its more delicate and less dichotomous ribbing, its more rounded, thinner, and less angular shell, and in the absence of crenulations over most of the margin, due to the feebleness of the sculpture. Modiolus (Brachydontes) demissus Dillwyn. Mytilus demissus (Solander MS.) Dillwyn, Descr. Cat. Rec. Shells, i., p. 314, 1817; Say, Journ. Acad. Nat. Sci. Phila., ii., p. 265, 1822; Wood, Ind. Test., p. 25, pl. 12, fig. 30, 1825 ; Greene, Mass. Cat., 1833; Ravenel, Cat., p. 7, 1837. Modiola plicatula Lam., An. s. Vert., vi., p. 113, 1819; ed. Desh., vii., p. 22, 1835 ; Totten, N. Engl. Cat., 1833 ; Gould, 1st Rep. Geol. Me., p. 119, 1837 ; Inv. Mass., p- 125, fig. 81, 1841 ; De Kay, Nat. Hist. N. Y., Moll., p. 184, pl. 24, fig. 258, 1843 ; Verrill, Inv. An. Vineyard Sound, p. 693, pl. 31, fig. 238, 1873; Dall, Bull. U.S. Nat. Mus., No. 37, p. 38, pl. 54, fig. 1, 1889. FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA 795 Mytilus plicatulus Sby., Genera, Myt., pl. vii., 1822; Deshayes, Enc. Méth., ii., p. 568, pl. 220, fig. 5, 1830; Stimpson, Sh. N. Engl., p. 12, 1851. Modiola semicostata Conr., Journ. Acad. Nat. Sci. Phila., vil., p. 244, pl. 20, fig. 7, 1837. (Not of Dall, Bull. 37, 1889.) Modiola semicosta Verrill (as of Conrad), Inv. An. Vineyard Sound, p. 693, 1873. (2) Mytilus clava Meuschen, Mus. Gronov., 1778 (fide Morch, Cat. Yoldi, ii., p. 54, 1853). (2) Mytilus magellanius Meuschen, Mus. Gevers, 1787 (fide Morch, of. cit., p. 54, 1853). Brachydontes clava Mérch, Cat. Yoldi, ii., p. 54, 1853. Perna (Brachydontes) plicatwla H. and A. Adams, ii., p. 517, 1857. Modiola demissa Conrad, Am. Journ. Sci., 2d Ser., ii., p. 44, 1846. Pliocene marls of the Caloosahatchie River, Florida, rare, Dall; Post Pliocene of Massachusetts Bay; recent from Nova Scotia to Georgia, west Florida, and Texas; locally restricted towards the extremes of its distribution. There is no doubt of the applicability of Dillwyn’s name to our common plicate mussel. The two names of Meuschen are doubtful, and probably cover a confusion of our species with the JZyzilus magellanicus of authors. I have not been able to consult Meuschen’s works, but believe the names are not accompanied by any description or figure, and are identified chiefly by means of the alleged localities. At all events, until the information is fuller and more satisfactory, it seems inadvisable to use Meuschen’s earlier name, while his later one is inapplicable. There are two distinguishable geographical races of this species, the form found north of New York, and figured in the Encyclopédie Méthodique, which Lamarck called plicatulus and Conrad semit- costatus ; and the southern form, which is more attenuated behind, has a more delicate and elegant sculpture, the ribs being minutely granulose, and the color lighter and of a less intense purple. Dillwyn’s name included both, and may be specially centred on the southern form, while that of Massachu- setts Bay may be regarded as forming a variety plicatulus. In my Bulletin 37, United States National Museum, the two names were accidentally trans- posed. Modiolus (Braéchydontes) citrinus Bolten. Arca modiolus Linné, Syst. Nat., Ed. xii., p. 1141, 1767. Mytilus citrinus polydentatus, etc., Chemn., Conch. Cab., viii., p. 175, pl. 84, fig. 754, 1785. Mytilus flavicans (Sol. MS.) Humphrey, Mus. Calon., p. 43, 1797 (no description or figure). Mytilus citrinus Bolten, Mus. Bolt., p. 157, 1798; Ed. ii., p. 111, No. 45, 1819. Mytilus exustus Gmelin, Syst. Nat., vi., p. 3352, 1792; not of Linné. TRANSACTIONS OF WAGNER 796 TERTIARY FAUNA OF FLORIDA Modiola sulcata Lam., An. s, Vert., vi., p. 113, 1819 (not of Lam., Ann. du. Mus., 1807) ; Reeve, Conch. Icon., x., pl. 10, fig. 74, 1858. > Modiola Chemnitz Potiez and Michaud, Gal. Moll., 1838 ; fide Morch. Brachydontes modiolus Mérch, Cat. Yoldi, ii., p. 54, 1853. Mytilus cubttus Say, Journ. Acad. Nat. Sci. Phila., ii., p. 263, 1822; De Kay, Nat. Hist. N. Y., Moll., v., p. 183, 1843; Gibbes, Cat. S. Car., p. xxii., 1848 ; Binney’s Say, p- 90, 1858. Perna (Brachydontes) modiola HW. and A. Adams, Gen. Rec. Moll., il., p. 517, 1857. Pleistocene of south Florida and the Antilles ; recent from South Carolina (Gibbes) south to the Antilles and Rio Grande do Sul, Brazil (Ihering). This species, which is excessively abundant where it flourishes at all, is commonly known under Lamarck’s name of sz/catus. It is very similar to several of the nominal Tertiary species, and a full and good series of both will be required to determine how far the older forms can be discriminated. The absence of a really good series of the fossils of this group makes it impracticable to suggest any synonymy here, though probably some reduction in the number of species will be demanded with further study and material. The following list includes the species hitherto named. M. (B.) texanus Gabb, Proc. Acad. Nat. Sci. Phila. for 1861, p. 371; Harris, op. cit. for 1895, p. 46, pl. 1, fig. 2. This was originally described as Perna texana, and is from the Lower Claibornian and Midway Eocene. M. (B.) Safford: Gabb, Journ. Acad Nat. Sci. Phila., 2d Ser., iv., p. 395, pl. 68, fig. 30, 1860; Harris, Bull. Pal., iv., p. 49, pl. 3, figs. 4, 5, 1896. Midway Eocene. M. (B.) potomacensis Clark, Bull. U.S Geol. Surv., No. 141, p. 85, pl. 34, figs. 1 a-1c, 1896. Mideocene of Maryland. MW. (B.) alabamensis Aldrich, Bull. Pal., ii, p. 16, pl. 5, fig. 13, 1895; Harris, op. cil., ix., p. 47, pl. 7, fig. 9, 1897. Wood’s Bluff horizon, Chickasawan Eocene. M. (B.) mississippiensis Conrad, Journ. Acad. Nat. Sci. Phila., 2d Ser., i., p. 126, pl. 12, fig. 19, 1848. Lower Oligocene of Vicksburg, Mississippi. MW. (B.) contractus Conrad, Pac. R. R. Rep., v., Geol., p. 325, pl. v., fig. 35, 1855. Pacific coast Tertiary. Eocene? MW. (B.) ornatus Gabb, Pal. Cal., i., p. 184, pl. 24, fig. 166, 1865. Tejon Eocene of California. FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA M. (B.) multiradiatus Gabb, Pal. Cal., ii., p. 30, pl. 8, fig. 52, 1866. Miocene of California. (Volsella striata ““ Gabb,” Meek, S. I. Checkl. Mio. Fos., p. 7, 1864, is probably a provisional manuscript name for this species.) There is a fine species in the Arago beds (Claibornian) of Oregon, which is probably identical with one of the above; and I have another, as yet un- identified, from the Oligocene limestone of Jacksonborough, Georgia. In the absence of authentic specimens of several of the above-mentioned nominal species it would be imprudent to attempt to describe either of these as new, while the wretched quality of a number of the figures renders an identification from them impossible. Modiolus (Gregariella) minimus n. s. PLATE 35, Ficure 26. Shell small, broad, with turgid umbones in front, more or less attenuated behind; hinge-line arcuate, convex, the opposite margin nearly parallel and concave, surface as in JZ. opifex Say. Alt. 8, lat. 3.5, diam. 4 mm. This little shell is represented by a silicious pseudomorph, retaining but little of the external surface, from the Oligocene silex beds of Ballast Point, Tampa Bay, Florida; the form is, however, unmistakable, and affords the opportunity of recording this group from that horizon. Modiolus (Botula) cinnamomeus Lamarck. Mytilus cinnamominus, etc., Chemn., Conch. Cab., viil., p. 152, pl. 82, fig. 731, 1785. Modiola cinnamomea Lam., An. s. Vert., vi., p. 114, 1819; ed. Desh., vii., p. 25, 1835. Oligocene of the Chipola marl, Chipola River, Monroe County, Burns; of the silex beds at Ballast Point, Tampa Bay, Dall, and of Trinidad, West Indies; Pliocene marl of the Caloosahatchie, Dall; recent, nestling or boring into soft limestone rock or shell, from the vicinity of Cape Fear, North Caro- lina, to the West Indies. A valve from coral at Belize measures thirty-four millimetres in length, but it is usually smaller. Iam not able to determine whether the East Indian shell usually called M. fuscus Gmelin is the same or distinct specifically. The distribution of boring species is often very wide. It is certain, however, that Chemnitz’s specimens, on which Iamarck founded the species, were West Indian. It seems remarkable that this species should be found in the Oligocene, but I am not, from my present material, able to find any differential characters whatever from recent specimens of the same size. TRANSACTIONS OF WAGNER 798 TERTIARY FAUNA OF FLORIDA This form differs from Lzthophaga especially by the presence of a row of small but well-defined scars, extending in a radial manner towards the lower posterior basal angle of the shell, within the pallial line. These almost give the impression, when observed casually, of the presence of a pallial sinus. In the absence of fresh specimens of the animal I am unable to determine the function of these scars. There are a few species of Modiolus named in the literature which belong elsewhere. JZ. spiniger H. C. Lea (Trans. Am. Phil. Soc., ix., p. 244, pl. 35, fig. 30, 1845) is perhaps a Crenella,; the spines are probably due to some extraneous organism; it is from the Miocene of Petersburg, Virginia. JZ. subpontis Harris (Bull. Pal., iv., p. 49, pl. 3, fig. 6a, 1896), from the Midway Eocene of Georgia, has the aspect of a Modtolaria. M. houstonia Harris (Proc. Acad. Nat. Sci. Phila. for 1895, p. 46, pl. 1, fig. 1), from the lower Clai- bornian of Texas, is probably a Lzthophaga, and specimens from the Orange- burg District of South Carolina, referred to his species by Harris, are certainly so. It should be carefully compared with Z. swbalveata Conrad, from the Lower Miocene of Cumberland County, New Jersey. JZ tenuis Meyer (Ber. Senckenb. nat. Ges., 1886, p. 10, pl. ii., fig. 7) is a Crenella, and identical with C. latifrons Conrad (1860), from the Claibornian and Jacksonian Eocene of Alabama. Genus LITHOPHAGA Bolten. Lithophaga Bolten, Mus. Bolt., p. 156, 1798; Ed. ii., p. 109, 1819; Morch, Cat. Yoldi, P- 55, 1853. Lithophagus Megerle, Entwurf., p. 69, 1811; Dall, Bull. 37, p. 58, 1889. Lithodomus Cuvier, Regne An., li., p. 471, 1871. Lithotomus Nitsch, Ersch et Grub. Encycl., Sect. 1, p. 175, 1825; Voigt, Cuv. Thierr., ill., p. 616, 1834. Lithodoma Verany, Cat. An. Invert., p. 13, 1846. Lithodomus Fischer, Man. Conch., p. 969, 1886. Letosolenus Cpr., Mazatlan Cat., p. 130, 1856. Myoforceps Fischer, Man. Conch., p. 969, 1886. The type in each of the first three cases cited is Mytilus hthophagus Linné. This was a compound of two species, the most common and best known of which was the Mediterranean form, which received the specific name of dactylus from Sowerby. The genus may be divided into sections as follows: Lithophaga Bolten, s.s. Shell subcylindric, with nearly terminal beaks ; sur- face polished, with no calcareous incrustation. Type ZL. dactylus Sby. FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA 799 Adula H. and A. Adams, 1857. Shell rhombic, with subcentral beaks; sur- face polished, clean. Type L. soleniformis Orbigny. Letosolenus Carpenter, 1856. Shell like Lzthophaga, but building a doubly tubular spout to the aperture of its burrow, and therefore probably furnished with elongated tubular siphons. Type ZL. spatiosus Cpr. Myoforceps Fischer, 1886. Shell as in Lzthophaga, but the animal has the habit of depositing a calcareous crust on the exterior of the valves, which covers them smoothly and projects in a twisted process from the posterior end of each valve. Type L. caudigera Lamarck. Diberus Dall, 1898. Resembling A/yoforceps, but with two or more radial sulci extending backward from the beaks, with the incrustation plume like, arranged in a distinct pattern on the areas between the sulci, and, when projecting beyond the ends of the valves, apposited symmetrically, not alternate and twisted as in the last section. Type L. p/amula Hanley. The genus is commonly represented in the Tertiary rocks by casts of its burrows, but the shells are so thin and fragile as to be rarely preserved, Most of those here mentioned are silicious pseudomorphs which preserve the form and markings of the original shell. Lithophaga antillarum Orbigny. Lithodomus antillarum Orb., Moll. Cubana, ii., p. 332, pl. 28, figs. 12, 13, 1847 (Spanish edition and atlas, 1845). Modiola corrugata Phil., Abbild. und Beschr., ii., 147, pl. 1, fig. 1, 1846. Lithodomus corrugatus Reeve, Conch. Icon., x., pl. 1, fig. 1, 1858. Lithophagus dactylus Mérch, Cat. Yoldi, ii., p. 55, 1853; not of Sowerby, 1824. Lithophagus caribeus Dall, Bull. U. S. Nat. Mus., No. 37, p. 38, No. 81, 1889; not of Philippi. Oligocene silex beds at Ballast Point, Tampa Bay, Florida, Willcox and Dall; recent from Florida southward through the Antilles. The reason why this species has not turned up in later formations is probably the extreme fragility of the shell and the less favorable opportunities for preservation. It would naturally have been absent through the colder period of the Miocene. It is among the St. Domingo fossils collected by Gabb. Lithophaga nigra Orbigny. Lithodomus niger Orb., Moll. Cubana, ii., p. 331, pl. 28, figs. 10, 11, 1847 (Spanish edition and atlas, 1845). TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA 800 Modiola cartbea Phil., Abbild. und Beschr., iii., p. 20, pl. 2, fig. 5, 1847; Zeitschr. fiir Mal. for 1847, p. 116. Modiola antillarum Phil., op. cit., p. 20, pl. 2, fig. 4, 1847; Zeitschr., p. 116 (not of Orbigny ; young shell). Mytilus lithophagus Gibbes, 5. Car. Cat., p. xxil., 1848; not of Linné. Lithophagus nigra Morch, Cat. Yoldi, ii., p. 56, 1853. Lithodomus antillarum Reeve, Conch. Icon., x., pl. 2, fig. 7, 1857. Oligocene silex beds of Ballast Point, Tampa Bay, Florida, Dall; ’ recent at Bermuda, and from South Carolina southward through the West Indies to Rio Janeiro, Brazil. Lithophaga nuda n. s. PLATE 11, FIGURE 7; PLATE 35, FiGureE 27. Oligocene silex beds at Ballast Point, Tampa Bay, Florida, where it is the most common species, and its burrows, or their casts, very numerous. Shell large, thin, closely resembling Z. xzgra, but from which it may be instantly discriminated by the absence of all transverse or radial striation. Alt. 17 (?), lat. 50, diam. 15.7 mm. Few of the specimens retain the outer markings of the shell, but those that do are easily recognized by the smooth surface, only sculptured by incre- mental lines. From the Dzderus group, which also have unstriated shells, it is distinguished by its cylindrical form, large size, absence of sulcations and of the calcareous mantle. Lithophaga (Myoforceps) aristata Dillwyn. Mytilus aristatus (Solander MS.) Dillwyn, Cat. Rec. Sh., i., p. 303, 1817. ‘ Modiola caudigera Lam., An. s. Vert., vi., p. 116, 1819 ; (after Enc. Meéth., pl. 201, fig. 8) Phil., Abb., ii., p. 149, pl. 1, fig. 5, 1846. : Mytilus caudigerus Gibbes, Cat. S. Car., p. xxii., 1848. Lithodomus aristatus Forbes and Hanley, Brit. Moll., 11., p. 212, 1851. Lithodomus caudigerus Sby., Genera, Lith., fig. 4, 1824; Reeve, Conch. Icon., x., pl. ii., fig. 16, 1857. Lithophagus aristatus Stimpson, Checkl. Rec. Sh., p. 2, 1860. Lithophagus forficatus Ravenel, Proc. Acad. Nat. Sci. Phila. for 1861, p. 44; Tryon, Am. Mar. Conch., p. 188, 1873; Dall, Bull. U. S. Nat. Mus., No. 37, p. 38, 1889. Oligocene of the silex beds at Ballast Point, Tampa Bay, Florida; recent from Cape Fear, North Carolina, south to the West Indies, east to the Red Sea, west to Mazatlan on the Pacific coast of Mexico. Only fragments probably referable to this form were obtained at Ballast FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA 8oI Point, but its wide distribution, evidently antedating the present conformation of Central American and Mediterranean lands, is much in favor of its antiquity. Lithophaga (Diberus) bisulcata Orbigny. Lithodonus bisulcatus Orb., Moll. Cubana, ii., p. 333, pl. 28, figs. 14-16, 1847 (Spanish edition and atlas, 1845). Modiola appendiculata, Phil., Abbild. und Beschr., ii., p. 150, pl. 1, fig. 4, 1846. Mytilus attenuatus Gibbes, Cat. S. Car., p. xxii., 1848 ; not of Deshayes. Lithophagus appendiculatus Morch., Cat. Yoldi, ii., p. 56, 1853. Lithodomus appendiculatus Reeve, Conch. Icon., x., pl. 4, fig. 21, 1857. Lithodomus biexcavatus Reeve, op. cit., fig. 22, a—b. Lithophagus bisulcatus Dall, Bull. U. S. Nat. Mus., No. 37, p. 38, 1889. Oligocene of the silex beds at Ballast Point, Tampa Bay, Florida, Dall; recent from South Carolina southward to the Gulf of Mexico, West Indies, and Rio Janeiro, Brazil. This species was found in the silex beds not only with the shell pre- served or reproduced, but with a complete pseudomorph of the calcareous mantle in which the lime was replaced by silica. Among the species reported in the literature of the American Tertiary is L. claibornensis Conrad (Journ. Acad. Nat. Sci. Phila., 2d Ser., i., p. 131, pl. 14, fig. 27, 1848; Aldr., Bull. Pal., 2, p. 17, pl. 5, fig. 14, 1895), from the Clai- bornian ; LZ. gaznesenses Harris (Bull. Pal., 4, p. 50, pl. 3, fig. 7, 1896), from the Upper Midway Eocene of Georgia, which may be referable to Botula; L. meurva Gabb (Journ. Acad. Nat. Sci., 2d Ser., viii., p. 377, pl. 47, fig. 80, 1881), from the Pliocene of Costa Rica, which is certainly a Botula and very close to B. cinnamomea Lam.; and L. subalveata Conrad (Am. Journ. of Conch., ii., p- 73, pl. 4, fig. 4, 1866), from the lowest Miocene of New Jersey, a peculiar species with which A/odiola houstonia Harris (1895) should be carefully com- pared. L. dactylus Sby. is reported by Conrad (Am. Journ. Sci., 2d Ser., 1, p. 210) as having been found by Lyell in Georgia, but this is perhaps a mis- identification ; the species may have been L. nuda. The figure of Byssomia petricoloides Lea (Contr. Geol., p. 48, pl. 1, fig. 16, 1833) much resembles a chipped Lithophaga, and the suggestion of Gregorio that it is identical with L. claibornensis Conrad is plausible. Genus CRENELLA Brown. Crenella Brown, Ill. Conch. Gt. Brit., pl. 31, figs. 12-14, 1827; 2d edition, p. 75, pl. 23, figs. 12-14, 1844. Type ALytlus decussatus Montagu, 1808. TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA 802 Stalagmium Conrad, Fos. Tert. Form., p. 39, Oct., 1833. Type S. margaritaceum Conrad, 7. c. Tlippagus Lea, Contr. Geol., p. 72, Dec., 1833. Type LV. tsocardioides Lea, 7. c., pl. 2, fig. 50. Myoparo Lea, Contr. Geol., p. 73, Dec., 1833. Type JZ. costatus Lea, 7. c., pl. 2, fig. 51. Nuculocardia Orbigny, Moll. Cubana, il., p. 310, 1847 (Spanish edition and atlas, 1845). Type WV. divaricata Orb., ¢. c., p. 311, pl. xxvii., figs. 56-59. Crenellodon Edwards, MS. Syst. List., Edw. Coll. B. M., p. 14, 1891. Type Cvrenella pulcherrima Edw., MS. Oligocene, Brit. Not Crenella Sowerby, Conch. Man., p. 297, fig. 136, 1842. This interesting little group extends through the Tertiary and, owing to the little study given to its characters, has received many names. The shell is usually convex and ovoid, with more or less incurved beaks, a nacreous inner layer, thin epidermis which adheres closely to the shell, and a fine radial, often crossed by a concentric, striation. In young shells the provinculum is exceptionally well developed, sometimes recalling the hinge of Wzacula by its strong and projecting denticulations. If the shell is thin, these become obso- lete with growth, but in some species are replaced by a series of denticulations directly consequent on the impingement of the external sculpture on the car- dinal margin, thus repeating a second time in the same individual the process by which the provinculum was originally initiated in its ancestors. At least that is the way in which the writer interprets the facts. When the shell is thick, or when the external sculpture is very delicate, no secondary denticula- tions appear in the adult, which is then left with a practically unarmed hinge- line. The appearance of the provinculum is not dependent on the existence of external sculpture, but the secondary denticulations are so dependent. The exterior may be almost perfectly smooth and polished with only microscopic striation ; finely radially striate without decussation (like C. sericea), decussate, or with the radial sculpture strong and divaricate. Usually the sculpture is uniformly distributed over the surface, but occasionally there will be an area of unstriated separating two of striated surface, as in A/odio/aria, but without the impressed boundaries of the latter genus. The form of the foot and the short siphons separate Crenella generically from Modiolaria, as far as yet shown, but the modifications of the surface upon which the former has been divided into genera are, in the writer’s opinion, of little more than specific value. //ippagus is a thick shell with feeble sculpture, and therefore the provinculum is not succeeded by a series of secondary den- ticulations. Otherwise it is an ordinary rather obese Crenella. Stalagmium FREE INSTITUTE OF SCIENCE $03 TERTIARY FAUNA OF FLORIDA is a typical Crenella, and JLyoparo is, of course, a synonyme specifically and generically of Conrad’s form. Neceuwlocardia is only a well-observed, strongly crenulate Crenxel/la, and what else, if anything, the undescribed Crenellodon may be is unknown. Crenela margaritacea Conrad has for a synonyme C. costata Lea; C. iso- cardioidca Lea (as Hippagus) and C. latifrons Convad (-+ Modzola tenuis Meyer, 1887) are Claibornian. The last mentioned is a large, oblique, thin species, and extends into the Jacksonian. C. concentrica Gabb (Pal. Cal., i, p. 186, pl. 24, fig. 169) is extremely similar to C. margaritacea and is found in the Martinez Eocene of California. A shell which is perhaps a Crenella (or a Lim@a) was described from the Miocene of Petersburg, Virginia, by H. C. Lea under the name of WMacula equilatera. Crenella divaricata Orbigny. Nuculocardia divaricata Orb., Moll. Cubana, ii., p. 311, pl. 27, figs. 56-59, 1847 (Spanish edition and atlas 1845) ; Gabb, Geol. St. Domingo, p. 252, 1873. Crenella decussata Dall, Blake Pelecypoda, p. 235, 1886. Oligocene of St. Domingo and Pliocene of Costa Rica, Gabb; Pliocene of the Caloosahatchie and Shell Creek, Florida, Dall and Willcox; recent from Cape Hatteras to the West Indies (one hundred fathoms off Barbados), and also on the Pacific coast at Panama and in the Gulf of California. This little shell is not to be distinguished, except by its nearly white color, from the young of C. decussata of the same size. The examination of a much larger series of specimens than was at my disposal when preparing the Blake report shows that the size when fully adult is uniform and always smaller than the adult C. decussata. The young divaricata is proportionately less inflated and has a more circular outline than the full-grown shell. The ‘color is yellowish or nearly white in all the specimens I have seen, and the epidermis hardly perceptible. Crenella minuscula n. s. PLATE 35, FIGURE 22. Oligocene of the lower bed at Alum Bluff, Chattahoochee River, Florida ; Burns. Shell minute, thin, inflated, elongate ovate, feebly radially striated, the striations apparently diverging from a medial line on the disk; not dichoto- mous; the beaks smooth ; inner margins crenulate; valves nearly equilateral. Alt. 1.75, lat. 1.25, diam. 1 mm. 16 TRANSACTIONS OF WAGNER S04 TERTIARY FAUNA OF FLORIDA This little shell is rare in the marl, and resembles in a general way C. diwartcata Orb., of which it is the precursor, but has fainter sculpture and smooth beaks, besides being constantly of smaller size, and is more narrow in form than the young of C. divaricata of the same length. Crenella duplinensis n. s. PLATE 35, FIGURE 6. Miocene of the Natural Well, Duplin County, North Carolina; Burns. Shell small, thin, rounded ovate, delicately radially sculptured, with fine, rounded ribs crossed by delicate incremental lines; smoother towards the beaks ; valves moderately inflated; beaks recurved, striae diverging from a line near the anterior third; inner margin crenulated, the crenule extending well up into the valve; the hinge with its crenulations short and delicate. Alt. 2.9, lat. 2.4, diam. 1.5 mm. This species is proportionally wider and less inflated than C. mnuscula, attains a larger size, and has more recurved beaks. From C. adivaricata it differs by its feebler sculpture, somewhat smaller shell, and especially by its much weaker hinge, with less conspicuous and strong crenulations. The line of divarication of the sculpture is also more anterior and the beaks more recurved. The recent Crenella glandula Totten is reported as fossil in the Pleisto- cene beds at Montreal by Dawson (Geol. Rep. Can., 1863, p. 927), and at Sankoty Head, Massachusetts, by Verrill, but Dr. Dawson is now disposed to refer his specimens to C. faba Fabr. Genus MODIOLARIA Beck. Modtolaria Beck, in E. Robert, Zool. Voy. Récherche en Isl. et en Gronl., pl. 17, figs. 1-4, 1840 ; Lovén, Ind. Moll. Scand., p. 33, 1846. Type JZytedus discors Linné. Lanistes Swainson (as of Humphrey), Malac., p. 385, 1840; not of Montfort, 1810. Type Mytilus tmpactus Herrmann. Lanistina Gray, P. Z. S., 1847, p. 199 (in place of Lanzstes Sw.). Modiolacra Gray, in Dieffenbach, N. Zeal., ii., p. 259, 1843 ; fide Hutton, Cat. Mar. Moll. N. Zeal., p. 78, 1873; (a typographical error for Modzolaria ?) sole ex. M. tmpacta Gray. Swainson quotes Lazzstes as of Humphrey, but there is no such genus in the Museum Calonnianum, where the Mytilus discors Lam. (not of Linne), otherwise JZ impactus Herrmann (1776), is given the specific name of FREE INSTITUTE OF SCIENCE 805 TERTIARY FAUNA OF FLORIDA “ Lanatus.’ By some confusion of this with Montfort’s Zanzstes (which is cited by Swainson, p. 387, as Lanites) this error probably arose. I have not access to Dieffenbach’s New Zealand at this writing, but if the Modolacra cited from it by Hutton is correct, it is probably a typographical error for Modtolaria, and. an earlier citation of Beck’s name than is usually known. This genus is distinguished from Cvenella by its elongated siphons, the branchial one being usually shorter and not closed along its lower side, but merely with apposited free edges; the foot also differs, being long and taper- ing to a point, instead of clavate as in Crenella. It is somewhat difficult to apportion the fossil species, but they are perhaps best separated from Crenella by the impressed mid-lateral area which, in the typical Jodzolaria, is usually smooth or not radially sculptured. The genus may be divided as follows: Modiolaria s.s. Shell with three areas on the disk, the central with feeble or entirely without radial sculpture, the others radially sculptured. Branchial siphon considerably shorter than the anal. Type Mytilus discors L. = MM. discrepans Mont. Lioberus Dall. Shell with the radial sculpture obsolete or absent; branchial siphon equal or nearly equal to the anal, both much elongated. Type Modiola castanea Say, Journ. Acad. Nat. Sci. Phila., ii., 266, 1822.* Rhomboidella Monterosato (1884). Shell rhomboid, the surface entirely covered with sharp radial striations. Type J/odiola rhombea Berkeley. ? Planimodiola Cossmann (1887). Shell modioliform rather than rhomboid, with the anterior radiated area very small and the valves rather com- pressed. Type Modtola sulcata Lam. (Parisian Eocene.) This section might quite as well be placed in JM/odiolus, from which it differs by no very important characters. It is very doubtful if it is a M/odiolaria. The type is not the same as the recent J/odiola sulcata of Lamarck (= JV. (Brachydentes) citrinus Bolten). The earliest species in our Tertiary is probably JZ subpontis Harris, from the Upper Midway, though its generic position is not positively determined. * This is probably the same as JZ. “igwea Reeve, Conch. Icon., x., A/odiola, pl. 10, fig. 71, 1858. MW. castanea Say was mistakenly referred by Tryon to the young of JZ tu/ipa Lam. in Am. Mar. Conch., p. 187, 1874. TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA M. alabamensis O. Meyer, from the Claibornian, is, however, a well-character- ized species. Modiolaria sp. indet. Oligocene of the Chipola River, Monroe County, Florida; Dall. A single broken valve belonging to this genus was obtained from the Chipola marl. It is a species similar to JZ. /ateralis Say, but marked especially by well-developed latticed sculpture in the interspaces of the radii. Modiolaria virginica Conrad. Modiolaria virginica Conrad, Am. Journ. Conch., ii1., p. 267, pl. 22, fig. 3, 1867. Yorktown, Virginia, Conrad; from the Miocene beds along the York River, Virginia, Harris. This small species is well-characterized by its rather angular shape, the reticulated sculpture of the posterior area, and the feeble sculpture of the anterior area. It recalls Gregariel/a, and perhaps should rightly be referred to that section of Modiolus rather than be placed in J/odiolaria. Modiolaria carolinensis n. s. ? PLATE 35, FIGURE 12. Upper Miocene of the Natural Well, Duplin County, North Carolina; Burns. Shell small, plump, rather elongate, with a shallow but well-marked radial furrow at the posterior edge of the medial smooth area; terminal areas radiately sculptured with small, radial, rounded threads, those on the anterior area fine and simple, those on the ridge of the posterior slope more or less reticulated by concentric elevated lines and distally dichotomous, divergent from the summit of the ridge and stronger dorsally; hinge-line straight, the margin above it angulated at its posterior termination; the beaks nearly anterior, the posterior ventral termination of the valve rounded and produced ; inner margin crenulated; on the hinge-line the crenule are almost like teeth, and increase in strength backward, distally being disproportionately large at the end of the series. Alt. 4.5, lat. 6.5, diam. 3.5 mm. This shell is very like JZ virginica, which, however, is arched instead of angulated near the distal end of the hinge-line, and, in the specimens I have been able to examine, is more rounded and less produced behind and has a less conspicuous medial furrow. It may, however, prove, when a sufficiently large number of specimens are brought together, that these characters fall FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA 807 within the limits of varietal rather than specific distinction. The specimen figured is somewhat blunted by fracture or other accidental causes at the lower posterior end, so that it does not show as much of the produced char- acter as the other smaller and less developed specimens which were collected with it. Modiolaria lateralis Say. Mytitlis lateralis Say, Journ. Acad. Nat. Sci. Phila., ii., p. 264, 1822; Binney’s Say, p. gi, 1858. Crenella lateralis Tryon, Am. Mar. Conch., p. 190, pl. 40, fig. 523, 1874. Modiolaria lateralis Dall, Bull. U. S. Nat. Mus., No. 37, p. 40, pl. 6, figs. 7, 8, 1889. Modiola elliptica H. C. Lea, Am. Journ. Sci., xliii., p. 106, pl. 1, fig. 2, 1842. Pliocene of the Caloosahatchie and Shell Creek marls, Florida, Dall and Willcox; Pleistocene of Simmons Bluff, South Carolina, Burns; recent at Portland, Maine (Fuller); Delaware Bay, Lea; North Carolina, United States Fish Commission; South Carolina, Gibbes; and southward through the Antilles to Venezuela ; situs on oysters and sponges (TZe¢hya). This pretty little species is much like JZ smarmorata Forbes of the British fauna. It is probable that specimens obtained north of Chesapeake Bay have been transported with “seed” oysters. Modiolaria translucida Gabb (Journ. Acad. Nat. Sci. Phila., 2d Ser., viii., p. 377, pl. 47, fig. 81, 1881) from the Plio- cene of Costa Rica is a very similar species. The recent northern species, JZ. nigra Gray and MW. discors L., are reported by Dawson (Can. Nat., 2, p. 419, and Geol. Rep. Can. for 1863, p. 927) from the Pleistocene glacial beds of the Province of Quebec, near Montreal. Famity DREISSENSIIDE. The systematic position of this family cannot yet be said to be definitely fixed, and is not likely to be finally decided until careful anatomical and embryological investigations of such forms as Sepétifer, Mytilopsis, etc., are available. The nomenclature of this group has, so far as I know, never been pub- lished in the full and precise shape demanded by systematists of the present day ; those who have referred to it seem to vie with each other in omitting dates, references, and essential facts. To make such a review here is not called for by present necessities, and is impracticable for want of part of the literature. The earliest name appears to be Exocephalus (Minster MS., 1828) Keferstein (Geogn. Geol. Zeitschr., ix., p. 92, 1831), but it would seem as if the TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA 808 genus had not been specifically characterized, though two species were de- scribed under this generic name, and it was cited by Deshayes (Bull. soc. géol. de Paris, t. iii.) in 1833. In 1836 Goldfuss fully characterized the genus, which was founded on two fossil species. In 1835 the recent Mytilus fluviatilis of Pallas (JZ. wolge@, Chemn., xi., p. 256, fig, 2028) was almost simultaneously named Drezssena (mel. Dreissensia) by Van Beneden and Tichogonia by Ross- massler, the former having a few weeks’ precedence. In 1837 appeared the names MZytilina and Mytilomia Cantraine. Jay, in 1836, used for the Danubian shell the name Dythalmia danubiit (Cat. Coll., p. 25) but without description. There is also a large number of variants due to misprints or errors of the pen. The species D. fluviatilis (or polymorphus of many authors) differs from most of the fossils and from our American shells by the absence of the secondary myophore, and is doubtless generically distinct. Being unable to determine the status of Exocephalus, the nomenclature of the American type may be provisionally stated as follows: Genus CONGERIA Partsch. Congeria Partsch, Ann. Wiener Mus., i., p. 93, 1835. Mytilops?s Conrad, Proc. Acad. Nat. Sci. Phila. for June, 1857, p. 167. Type JZ Zeuco- pheatus Conr., 1831. Mytilus sp. Reeve, Conch. Icon., x., pl. x., 1858. Praxis H. and A. Adams, Gen. Rec. Moll., ii., p. 522, Dec., 1857. Mytiloides Conrad (/apsus), Proc. Acad. Nat. Sci. Phila. for 1874, p. 29 ; not of Brogniart, 1822. Partsch specifically mentions the myophore in his diagnosis, and an ex- amination of a number of his species shows that they agree in all essential systematic characters with the American shells. Congeria leucophzeata Conrad. Mytilus leucopheatus Conrad, Journ. Acad. Nat. Sci. Phila., vi., p. 263, pl. 11, fig. 13, 1831 ; Ravenel, Cat., p. 7, 1834; De Kay, New York Fauna, Zool., v., p. 184, 1843. Mytilopsis leucopheatus Conr., Proc. Acad. Nat. Sci. Phila. for 1857, p. 167; Dall, Bull. U. S. Nat. Mus., No. 37, p. 40, 1889. Dreissena americana (Recluz MS.), in Reeve, Conch. Icon., x., pl. x. (AZvtzlus), fig. 43, Jan., 1858; Fischer, J. de Conchyl., vii., p. 131, 1858. Dreissena Riisti (Dkr. MS.) Fischer, Journ. de Conchyl., vil., p. 133, 1858. Dreissena leucopheta Tryon, Am. Mar. Conch., p. 190, pl. 40, fig. 424, 1874. Pleistocene of North Beach, Osprey, Florida, Dall; recent, especially FREE INSTITUTE OF SCIENCE 809 TERTIARY FAUNA OF FLORIDA about oyster beds, from Maryland to Florida, Nicaragua (Richmond), New Grenada (Totten), St. Thomas (Dunker), and Vieque, West Indies. A review of the American Congerias in the National Museum shows that besides the above-mentioned species there is found in the United States the C. Rossmdssleri Dunker (1858, Rve., fig. 45, + C. Salle: Reeve, fig. 44, 1858, not of Recluz, 1852), which occurs near Tampa, Florida, and is said to extend to Brazil. It is distinguishable from the common /eucopheata by its more triangular, anteriorly flattened, heavier shell. The C. Gundlachi Dunker (1858), which has a more conspicuous myophore, is found in Cuba, while the C. cochleata is common at Colon, on the Isthmus of Darien. There may be one or two more identifiable forms in the West Indies, but the shell is variable, passing through about such a set of mutations as does JZytzlus edulis, and too much stress should not be laid on slight differences. None of the other species mentioned has yet been found fossil, but a species is not uncommon in the Florida Pliocene which is obviously different from any of them. It is notable that the European type, Drezssensia, does not occur in Africa or America, though it is represented by a species (2. Massiez L. Morlet) in Cochin China. In Africa, America, China, and the Viti Islands Congeria is present. Congeria lamellata n. s. PLATE 35, FIGURES 13, 14, 15. Pliocene marls of the Caloosahatchie and Shell Creek, Monroe County, Florida; Dall and Willcox. Shell subtrigonal, externally smooth, except for concentric undulations due to irregularities of growth; anterior side flattened below the beaks, the periphery of the flattened area rounding over towards the disk; beaks subacute and slightly twisted outward, byssal gape very narrow; dorsal slope sub- arcuate with no pronounced angle at the distal end of the hinge-line, in the vicinity of which the valves are somewhat compressed; internal margins smooth; cardinal border with a wide groove for the reception of the ligament, this groove being continuous to the beaks; septum small, separated from the groove by a /\-shaped lamella which on the anterior side is conspicuously produced and extends along the anterior margin about twice the length of the septum beyond the septum; myophore small, entirely hidden below the septum and formed by a callous eminence bearing the scar of the retractor muscle of the foot upon which the strain from the byssus comes; adductor TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA 810 scars ovoid, elongate, and partly in contact, with a slight insinuation of the pallial line in front of them; margin of the right valve somewhat impressed below the beak so as to pass behind the prominence on the margin of the opposite valve when closed. Alt. 17, lat. 10, diam. 10 mm. This is a much heavier and more triangular shell than C. /eucopheata and more elongate than C. Rossméssleri, with a different hinge from either. Some very similar but not conspecific forms occur in the Vienna basin. Harris mentions the occurrence of a Drezssensia (= Congeria) in the Galveston artesian well, between the levels of two thousand one hundred and twenty-three and two thousand eight hundred and seventy-three feet below the surface. The horizon here is Upper Miocene. There are no species of Seftfer determined from the Tertiary rocks of eastern North America, but, as elsewhere noted, Cooper has described a species from the Californian Tertiary. Famity JULIIDAE. (Prasinid@, p. 529.) This family has not been hitherto represented in the faunal lists of American mollusks, recent or fossil, except through the inclusion of forms such as Phaseolicama and certain Paleozoic fossils, which in all probability belong elsewhere. Semper showed many years ago that the typical genus, Prasina, was suspiciously close to the older genus, Julia, of Gould. Fischer, in his manual, unites them as subdivisions of one genus. They are really identical, and the consolidated genus must take the older name of Gould and Prasina be relegated to synonymy, according to the rules of nomencla- ture. To Prasina and Julia Cossmann has added a shell from the Parisian Eocene, named by him Axomalomya, and Fischer has suggested that Berthe- linia Crosse may perhaps find a place in the same vicinity. Genus JULIA Gould. Julia Gould, Proc. Bost. Soc. Nat. Hist., vili., p. 284, Feb., 1862; Otia, Conch., p. 241, 1862. Type /. exguisita Gould, 7. c. Prasina Deshayes, Cat. Moll. Isle de Réunion, p. 25, 1863. Type P. borbonica Desh., op. cit., p. 29, pl. iv., figs. 4-8. Prasinia Cossmann, Cat. Ill. Eoc. Paris, p. 174, 1887. Fischer (Man., p. 950) separates Prasina from Julia on the ground that the latter is nacreous and has the borders finely crenulated, but both these FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA SII characters are non-existent in the one as much as in the other. Gould prob- ably used the word “margaritacea” to express the lustre often seen on polished porcellanous shells, and the “crenulations” are merely the faint incremental radiations common to all bivalves. The examination of authentic specimens of Gould’s species (for which I am indebted to the authorities of Cornell University) enables me to make a positive statement in regard to these facts. The shell is zo¢ pearly and the margin is of crenulated in the strict sense of those words. The adductor scar is precisely as figured by Fischer for Prasina borbonica, and I can find no trace of any other scar, though the interior is so polished that this would be hardly visible at any rate if present. Julia floridana n. s. PLATE 35, FIGURES I, 2, 3. Oligocene marl of the Chipola River, Florida; Burns. Shell small, inflated, smooth, arched above, rounded behind, the base nearly straight; the beaks prominent with a small impressed lunule imme- diately under them; below this lunule the valve projects forward to a rather acute point; with the exception of the groove for the ligament the hinge-line is perfectly simple without teeth or crenulations of any kind; the edge of the impressed lunule in the right valve is produced into a lamella which fits behind a less prominent extension of the corresponding margin in the opposite valve ; interior of the valves smooth, with no trace of muscular or other scars; exterior sculptured only by faint incremental lines; inner margin of the valves simple, not crenulated; shell substance showing no traces of nacreous struc- ture, but rather porcellanous. Alt. 4.5, lat. 6.5, diam. 2 mm. This species evidently belongs to the same restricted group asthe original Prasina borbonica of Deshayes. The chief difference is that the impressed lunule is smaller and not so deep, and that its margin in the left valve is not elevated into so evident a tubercle. Careful scrutiny of more than twenty valves collected failed to show any satisfactory muscular or pallial scars. This is the only species known from American deposits and, as far as I have been able to discover, the only fossil species known of the restricted group from any horizon. TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA 812 Order TELEODESMACEA. For reasons of convenience, some groups of this order having been completed in manuscript as much as two years ago, and it being desirable to print them as early as practicable, the series of families is here begun with the Zeredinide, an order the reverse of that appearing in the list of families en page 484 of this volume. Superfamily ADESMACEA. Famiry TEREDINID/E. Genus TEHREDO Linné. Teredo Linné, Syst. Nat., Ed. x., p. 651, 1758. Type 7. zavafis Linné. Xylophagus Meuschen, Zooph. Gronovianum, p. 258, 1781. Same type. The tubes of Zeredo and its allies appear in all the Tertiary horizons of North America which have been well searched, and a number of names have been applied to them, but so far, I believe (unless Pholas rhomboidea Lea, from the Miocene of Petersburg, Virginia, be founded on a valve of Zeredo), the valves of none of the species have been described or figured. This leaves the species of the genus in our Tertiary in a very unsatisfactory state, and it has even been suspected that some of the tubes described as teredine are really the shelly retreats of Serpulide or other tubicolous worms. In this uncertainty, I shall content myself with giving a list of the names which have been proposed, with references, leaving to a more propitious time the task of examining into their validity or determining their synonomy. Eocene. 1. Teredo emacerata Whitfield, Lam. N. J., p. 242, pl. xxx., fig. 25, 1885. Eocene marl of New Jersey. N Teredo mississippiensis Conrad, Wailes, Geol. Miss., p. 289, 1854; Eoc. Checkl. S. I., p. 24, 1866 (name only). Upper Eocene of Jackson, Mississippi. 3. Teredo pugetensis White, Bull. U. S. Geol. Surv., No. 51, p. 62, pl. 8, fig. 1, 1889. Eocene of the Puget Group, Puget Sound, Washington, from Carbonado, Washington. 4. Teredo simplex Lea, Contr. Geol. p. 38, pl. 1, fig. 6, 1833. Claiborne sands at Claiborne, Alabama. FREE INSTITUTE OF SCIENCE O 813 TERTIARY FAUNA OF FLORIDA This species is represented by a short piece of tube, apparently teredine, among Lea’s types. De Gregorio, however (Mon. Claib., p. 10, pl. 1, figs. 30-33), has identified what he regards as a Serpul/a tube from Claiborne with Lea’s species, and for the true Zeredo tubes which occur in the Claiborne sands has proposed the name of Zeredo siniplexopsis (op. cit., p. 236, pl. 38, figs. 26 a—0, 1890), which probably may have to be regarded as a synonyme of T. simplex, while the Serpula will need a new name. 5. Teredo substriata Conrad, Geol. U.S. Expl. Exp., p. 728, pl. 20, figs. 7 a—-3, 1849. Tertiary of Astoria, Oregon. . Teredo virginiana Clark, Bull. U. S. Geol. Surv., No. 141, p. 72, pl. 15, figs. .5§ a-c, 1896. Eocene of Virginia and Maryland. Oligocene. . Teredo incrassata Gabb (as Kuphus), Geol. St. Domingo, p. 249, 1873; Journ. Acad. Nat. Sci. Phila. 2d Ser., viii., p. 342, pl. 44, figs. 12 a-c, 1881. Oligocene of St. Domingo, Haiti, and Costa Rica, Gabb; and of the Bowden marls, Jamaica, Henderson and Simpson. TZ: /istula Guppy (zoz H. C. Lea), from the Oligocene of Trinidad, is probably the same. . Teredo circula Aldrich, Bull. Ala. Geol. Surv.,i., p. 36, 1886. Vicksburgian. Miocene. . Teredo calamus H. C. Lea, Trans. Am. Phil. Soc., 2d Ser., ix., p. 234, pl. 34, fig. 4, 1845. Petersburg, Virginia. TZ: fistula of the same author (a. cit, fig. 5) is probably identical, being from the same locality and differing in little but size. . Teredo (sp.) Conrad, Am. Journ. Conch., v., p. 101, 1870, is cited from the Miocene of New Jersey. . Teredo (sp.) Merriam, Bull. Univ. Cal., ii., No. 3, p. 104, 1896. Miocene of Vancouver Island; should be compared with 7: substriata Conrad. A species of Zeredo or some allied genus is abundant in the fossil wood of the Miocene at Unga Island, Alaska. Pleistocene. . Aylotrya palmulata Leach is reported by Holmes (Post-Pleioc. Fos. S. Car., p- 60, pl. 9, fig. 5, 1858) from the Pleistocene of South Carolina. TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA Famity PHOLADID. This family is in much the same condition as regards the Tertiary American species as the preceding, except that the shells are better known. They are as a rule rare, the specimens more or less imperfect, and often unique, and widely scattered in different collections. Only a few can be considered in detail here, but they will be followed by a list of the species mentioned in the literature. The most thorough revision of the species of the group as regards synonymy is to be found in Tryon’s Monograph of the Pholadacea, a reprint of papers extracted from the Proceedings of the Academy of Natural Sciences, Philadelphia, 1861-62, though some shifting of generic names would be necessary to bring the work up to date. Subfamily PHOLADINZ Tryon. Anterior hiatus permanently open, with no callum. Genus PHOLAS (Linné) Lamarck. Pholas Linné, Systema Nat., Ed. x., p. 669, 1758 (er parte); Lam., Prodrome, p. go, 1799. Type P. dactylus L. Dactylina Gray, P. Z. S., 1847, p. 187; Tryon, Mon. Pholad., p. 75, 1862. Phragmopholas Fisher, Man. de Conchyl., p. 1133, 1887. Thovana (Leach MS.) Gray, P. Z. S., 1847, p. 187. Valves with an umbonal reflection, the space beneath it divided into cellular cavities by supporting radial septa. Subgenus PHOLAS s. s. Shell with an accessory protoplax, a mesoplax with the nucleus at the outer margin over each umbo, and a narrow elongate hypoplax. Valves emarginate in front. Type P. dactylus L. Subgenus THOVANA Gray, 1847. Like Pholas, but with the mesoplax nucleus near the inner margin and the valves regularly rounded in front. Type P. oblongata Say. This is Gitocentrum Tryon, 1862, and based on the same type. Subgenus MONOTHYRA Tryon, 1862. The shell with a single mesoplax over both umbones with a subcentral nucleus, the anterior hiatus narrow. Type P. ortentalis Gmelin. FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA . Pholas (Thovana) campechiensis Gmelin. Pholas campechiensts Gmelin, Syst. Nat., vi., p. 3216, 1792; Hanley, Descr. Cat. Rec. Sh., p. 6, pl. 9, fig. 44, 1842. Pholas oblongata Say, Journ. Acad. Nat. Sci., ii., p. 320, 1822; not of Tuomey and Holmes, Pleioc. Fos. S. Car., p. 103, pl. 24, fig. 5, 1858. Pholas candeana Orbigny, Moll. Cubana, p. 215, pl. 25, figs. 18-19, 1845. (Young shell.) Pleistocene of South Carolina and Florida; recent from Cape Hatteras, North Carolina, to Brazil. This species is distinguished from the following one by the proportions and extent of the umbonal processes, which differ markedly in the two forms. Pholas (Thovana) producta Conrad. Pholas oblongata Tuomey and Holmes, Pleioc. Fos. S. Car., p. 103, pl. 24, fig. 5, 1858; not of Say. Photas producta Conrad, Proc. Acad. Nat. Sci. Phila. for 1862, p. 571, 1863. Miocene of the Sumter District and Peedee River, South Carolina; Plio- cene of the Waccamaw River, South Carolina; Holmes and Johnson. In this species the umbonal reflection is considerably longer in proportion than in the Pleistocene shell, and the anterior space between the reflected edge and the exterior of the valve in front of the umbo and below the level of the septa is much smaller and less conspicuous. The ribbing of the present species is less sharp and continuous. Pholas (Thovana?) Memmingeri Tuomey and Holmes. Pholas Memmingeri TY. and H., Pleioc. Fos. S. Car., p. 104, pl. 24, fig. 6, 1858. Miocene of the Sumter District, South Carolina; Tuomey and Holmes. This species recalls Z7f@a, but is said by the authors cited to have a septate umbonal reflection. It is subtruncate behind and differs widely from any of the other species, but has been unaccountably omitted from all the checklists. Genus BARNEA (Leach MS.) Risso. Barnea Risso., Hist. Eur. Mer., iv., p. 376, 1826. Type B. spinosa Risso (= P. candida Linné). flolopholas Fischer, Man. de Conchyl., p. 1133, 1887. Pholas Lamarck, 1801 ; Tryon, 1862 ; , not Lamarck, 1799. Cyrtopleura Tryon, Mon. Pholadacea, p. 73, 1862. Shell with the space below the umbonal reflection not septate; accessory plates not exceeding two in number. TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA 816 Subgenus BARNEA s. s. Shell with only one accessory plate (protoplax); anterior gape small. Type Pholas candida Linne. Subgenus SCOBINA Bayle, 1880. Shell with a transverse mesoplax and a lanceolate protoplax. Type P. costata Linné. Barnea (Scobina) costata Linné. Pholas costatus Linné, Syst. Nat., Ed. x., p. 669, 1758; Lam., An. s. Vert., v., p- 445, 1818; Sby., Gen., No. 23, pl. 1, 1824; Holmes, Post-Pleioc. Fos. S. Car., p. 58, pl. 9, figs. 1, 1a, 1858; Tryon, Mon. Pholad., p. 73, 1862. Pholas virginianus Lister, Hist. Conch., Ed. ii., pl. 5, fig. 434, 1770. Pliocene of the Caloosahatchie marls, Florida, Dall; Pleistocene of Mas- sachusetts, at New Bedford; of Maryland, at Cornfield Harbor; of South Carolina, at Simmons Bluff; of Florida, at Osprey; recent from Massachu- setts south to Mexico and Brazil. The recent shell is identical with that of the Pliocene, but differs from the Miocene form by its uniformly thinner texture, resulting in a sort of punctate pattern on the interior of the valves, its larger size, and the different proportions of its umbonal reflection, much as P. campechiensis differs from the Miocene P. producta. Barnea (Scobina) arcuata Conrad. Pholas arcuata Conr., Medial Tert., cover of No. 2, p. 3, 1841; Proc. Acad. Nat. Sci. Phila. for 1862, p. 571, 1863. Pholas acuminata Conr., Medial Tert., p. 77, pl. 44, fig. 2, 1845. Pholas costata Tuomey and Holmes, Pleioc. Fos. S. Car., p. 102, pl. 24, fig. 4, 1857; not of Linné. Miocene of Nansemond River, near Suffolk, Virginia, Burns; of Mary- land, Conrad; of South Carolina, in the Waccamaw district, Tuomey. This species is known from &. costata by its longer umbonal reflection and smaller size. It is usually more solid and thick, with more numerous and finer radial ribs. Fragments from the Galveston artesian well may be- long to it, but have not been accessible to me for critical comparison with B. costata. Barnea truncata Say. Pholas truncata Say, Journ. Acad. Nat. Sci. Phila., ii., p. 321, 1822; Sby., Thes. Conch., i., p. 488, pl. 104, figs. 29, 30, 1849; De Kay, Zool. N. Y., Moll., p. 248, pl. 34, fiz. 323 a—-6, 1843; Holmes, Post-Pleioc. Fos. S. Car., p. 57, pl. 9, fig. 4, 1858. Pholas (Cyrtopleura) truncata Tryon, Mon. Pholad., p. 74, 1862; Cat. Pholadacea, p. UO OTE FREE INSTITUTE OF SCIENCE 81 TERTIARY FAUNA OF FLORIDA 7 Pleistocene of South Carolina, Holmes; recent at New Bedford Harbor, Massachusetts, and southward to South Carolina, Ravenel; Chili and Peru, Ruschenberger (?) fide Tryon. This species (to which the figure of P. Memmingert T. and H. has a sus- picious resemblance) usually has a tolerably wide anterior gape, and a single accessory valve extending forward from behind the umbones with the nucleus posterior; but in one specimen in the National Museum the plate is divided into two, the anterior elongate and narrow, the posterior (behind the umbones) small and round, and this is the condition figured by De Kay. There seems to be no doubt as to the specific identity of the two variations, which leads to a query as to the systematic value of the characters upon which the name Scobina is based. The identity of the form from the west coast of South America with Say’s truncata is doubtful. Perhaps it should rather be united with the Californian type named by Stearns Pholas pacifica. Barnea alatoidea Aldrich. Pholas alatotdea Aldr., Bull. Ala. Geol. Surv., No. 1, p. 36, pl. 4, figs. 9 a—c, 1886. Pholas Ropertana Tuomey MS. Barnea alatotdea Cossmann, Notes Compl. Eoc. Ala., p. 5, 1894. Chickasawan Eocene of Bell’s and Gregg’s Landings, Alabama; Aldrich. De Gregorio has given the varietal name of A/drichz to the figure 96 of Aldrich. The species strongly recalls B. Levesquec Watelet of the Parisian Eocene. Genus ZIRFAGA (Leach) Gray. Zirfea ‘‘ Leach, 1817,’’ Gray, P. Z. L., 1847, p. 188; Ann. Mag. N. Hist., 2d Ser., viii., p- 385, 1851. Zirphea Leach, Moll. Gt. Brit., pp. 250, 252, 1852. Type Pholas crispata Linné. Thurlosia ‘‘Leach, Conch. Nomen., 1845,’’ fide Agassiz in Scudder’s Nomenclator, 1882; (not found.) Shell with a radial sulcus dividing the valves into two areas; accessory plates rudimentary or wanting ; anterior gape large. Zirfeea crispata Linné. Mya crispata Linné, Syst. Nat., Ed. x., p. 670, 1758. Pholas crispata Linné, Syst. Nat., Ed. xii., p. 1111, 1767. Pholas bifrons Da Costa, Brit. Conch., p. 242, pl. 16, fig. 4, 1778. Pholas parva Da Costa, Brit. Conch., p. 247, 1778. (Young shell.) Solen crispus Gmelin, Syst. Nat., vi., p. 3228, 1792. TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA 818 Pholas lamellata Russell, Essex Journ., 1., p. 50, 1839 (not Turton). Zirfea crispata Gray, Ann. Mag. Nat. Hist., 2d Ser., viil., p. 385, 1851. Zirphea crispata (Gray) Leach, Moll. Gt. Brit., p. 252, 1852. Thurlosia crispata Tryon, Mon. Pholadacea, p. 83, 1862 ; (not in Leach as cited by Tryon !) Miocene (?) of New Jersey near the mouth of Shark River, Whitfield (in United States National Museum); Pleistocene of Labrador and boreal eastern America; recent in northeastern America from the Arctic Seas south to New York and possibly to North Carolina. I have been unable to trace the 7urlosia synonyme further than Tryon. It does not occur in the Mollusca of Great Britain, from which he cites it. If Agassiz’s reference be correct it would antedate Zrphea and Zufea, but I can- not discover the publication to which he alludes, and therefore retain what appears to be the earliest identifiable name. There is some doubt as to the age of the New Jersey fossil; at least it has the appearance to me of being newer than the Miocene. The Pholas semicostata H.C. Lea, which in 1889 I referred with doubt to Ziufea, probably belongs with Zeredina. It is a very peculiar form, and the species has not yet been found in a fossil state. The Z2/ea from the northwest coast of America, referred by Carpenter to Z. crispata, is a distinct though allied species, called Z. Gabba by Tryon, and found fossil in the Pleis- tocene of California as well as living, there and northward. Another species, Z. dentata Gabb (Pal. Cal., ii., p. 18, pl. 3, figs. 31-31 @, 1866), is found in the Californian Pliocene. 7. plana White (Bull. U. S. Geol. Surv., No. 51, p. 15, pl. iv., fig. 22, 1889) is from the Tejon Eocene near Martinez, California. Subfamily JOUANNETINZ Tryon. Anterior gape closed in the adult by a calcareous deposit, or “ callum,” attached to either valve and the edges of which meet in the middle line below ; valves with one or more radial sulci, and with one or more accessory plates. Genus PHOLADIDEA Goodall. Pholadidea Goodall, in Turton, Conch. Dict., p. 147, 1819. Type P. Loscombiana Good- all (= Pholas papyraceus Turton, Dith. Brit., p. 2, 1822, + (?) Pholas papyraceus Solander MS., 1788). Cadmusia Leach, Moll. Gt. Brit., p. 254, 1852; same type. Shell with a double anterior accessory plate (protoplax), the other plates present or absent, the valves prolonged behind into leathery or testaceous cups or a tube (siphonoplax) for the protection of the siphons. FREE INSTITUTE OF SCIENCE 819 TERTIARY FAUNA OF FLORIDA Subgenus PHOLADIDEA s. s. Shell with a double, rather small, protoplax, the siphonoplax cup-like, the other accessory plates wanting; a single radial sulcus. Type P. Loscom- diana Goodall. Section Penztella Val., 1846. Like Pholadidea, but with a small mesoplax, the two parts of the proto- plax confluent. Type Pholas penta Conrad, 1838 (+ P. concamerata Desh., 1840, + P. Conrad, Val., 1846). Pholameria Conrad, 1865, is probably syn- onymous. Section WVettastomella Carpenter, 1865. Like Pholadidea, but small, with the siphonoplax prolonged as diverging flaps. Type P. Darwint Sowerby (= P. penita Tryon, not Conrad). Section A/atasta Gray, 1851. Like Pholadidea, but with the siphonoplax prolonged into a shelly tube. Type P. melanura Sowerby (= P. Wilsont Conrad, 1849). Genus PARAPHOLAS Conrad, 1849. Shell with a single large protoplax, the mesoplax and metaplax present, double but confluent; a double hypoplax present; valves with two radial sulci, the posterior becoming obsolete with age; the siphonal prolongations thin and horny, not attached to a heavy calcareous tube, which is formed from débris by the animal around the siphonal opening of its excavation ; this differs from the siphonoplax of Pholadidea in not being an original secre- tion of the animal. Type P. californica Conrad (+ P. Janell Desh.). Genus MARTESIA Leach. : Martesia Leach, in Blainville, Man. de Mal., i., p. 632, 1825. Type P. clavata Lam. = Pholas striata Linné. Shell with a large protoplax, elongated metaplax, and a double confluent narrow hypoplax; mesoplax and siphonoplax wanting ; valves with a single radial sulcus. This is one of the oldest and most prolific groups of Pholads, both in the Tertiary and existing faunas. The mutations which occur between youth and the adult condition in Pholads are so great that the young shell may sometimes be referred with equal plausibility to several genera, hence the references of our Tertiary forms following must be taken as merely provisional, 7 TRANSACTIONS OF WAGNER TERTIARY FAUNA OF FLORIDA These species appear to be referable to Pholadidea: P. (Pholameria) triquetra Conrad (1848) is a young shell from the Vicksburgian Oligocene and resembles a young Pholadidea. \t has no characters upon which the undefined genus Pholameria Conrad (1865) can be maintained. Pholadidea (PLenitella) penita Conrad, 1838 (+ P. spel@a Conr., 1855), and P. (P.) ovordea Gould, 1853, are known from the Pleistocene of California and may turn up in older horizons. Z2rf@a plana White, which is a young shell, may eventually find a place hereabouts. Parapholas is represented in the Eocene marls of New Jersey by P. Knetskernt Whitfield (Lam., Eo. N. J., p. 241, pl. 30, figs. 22-24, 1885); and in the later Tertiaries of California by P. californica Conrad, also found recent on the same coast. The genus A/artesia includes MW. elongata Aldrich, 1886, from the Chicka- sawan Eocene of Bell’s Landing, Alabama; JZ. ¢exana Harris, 1895, from the Claibornian of Texas; JZ clausa Gabb, 1866, from the Tejon Eocene of California; JZ striata Linné is reported by Guppy and Gabb from the Pliocene of Trinidad and Costa Rica; JZ cuneiformis Say, 1822, from the Miocene of Yorktown, Virginia, and the Pleistocene of South Carolina; and JZ. znter- calata Cpr., 1857, from the same horizon in California. M/artesia Dalli Harris, 1895, from the Midway Eocene of Georgia, appears from the figure to be more like a Gastrochena; it is certainly not a WMartesia. MM. spheroidalis Guppy, from Bowden, is probably referable to another group. The following species may be a Martesta, though there is no trace of any accessory valves except the protoplax. Martesia ? ovalis n. s. PLATE 36, FIGuRE 5. Miocene of Maryland, at Plum Point; Harris. Shell small, short; valves somewhat lozenge-shaped with a single, nearly median, radial furrow ; in front of the furrow the valve is covered with crowded, fine, somewhat pectinated lamellae ; behind, sculptured only with rather coarse concentric incremental lines; the posterior termination bluntly rounded; umbonal reflection small, solid, standing up vertically from the shell with a thickened edge; callum smooth, meeting that of the opposite valve without overlapping ; protoplax enormous, extending nearly as far back as the ends of the valves and similarly forward to the anterior ends, but broken here so that it is not certain how far it may have curved anteriorly; the lateral edges are FREE INSTITUTE OF SCIENCE TERTIARY FAUNA OF FLORIDA 821 not complete, but the general form seems to have been oval or rounded, with no signs of segmentation, furrows, or additional accessory plates, which, indeed, would be quite needless. Lon. 12, lat. 8.5, diam. 7 mm. This singular shell recalls Martesta obtecta Sby. in its enormous proto- plax. Say’s description of his Pholas ovals is insufficient to identify his shell without a figure or typical specimen. I have wondered if it could be possible that the “tube” in which his shell is said to have been enclosed could by any chance have been a poorly observed or imperfect protoplax of this kind. It is, of course, impossible to decide without further information, but Say’s descriptions are usually so clear and good, and his observing powers were so keen, that I can hardly suppose him to have used the word “tube” for an appendage of this kind without some explanation or modification. This species appears to be related to the Pholas scutata Deshayes (An. s. Vert. Bassin de Paris, 1., p. 137, pl. vi., figs. 5, 6, 1860), for which and similar species he proposed the sectional name Scutigera. This name being pre- occupied since 1802 for a genus of JZyriapods, Fischer proposed to replace it by